Communications method and device

ABSTRACT

Disclosed are a communications method and device. The method includes: sending, by a network device, configuration information to a terminal device; determining, by the terminal device, channel state information CSI measurement behavior and/or CSI feedback related information, where the channel state information CSI measurement behavior and/or the CSI feedback related information are/is related to the configuration information; and performing, by the terminal device, CSI measurement based on the configuration information and the CSI measurement behavior and/or the CSI feedback related information, to obtain at least one piece of CSI, and sending all or some of the at least one piece of CSI to the network device. It can be learned that, in a scenario in which a plurality of transmission modes are supported, according to the foregoing method, the terminal device can measure CSI, and feed back the measured CSI to the network device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/814,463, filed on Mar. 10, 2020, which is a continuation ofInternational Application No. PCT/CN2018/105094, filed on Sep. 11, 2018,The International Application claims priority to Chinese PatentApplication No. 201711125639.2, filed on Nov. 14, 2017 and ChinesePatent Application No. 201710812735.8, filed on Sep. 11, 2017. All ofthe afore-mentioned patent applications are hereby incorporated byreference in their entireties.

TECHNICAL FIELD

The present disclosure relates to the field of communicationstechnologies, and in particular, to a communications method and device.

BACKGROUND

Currently, transmission between a terminal device and a network devicesupports a single-point transmission mode and a coordinated multi point(CoMP) transmission/reception mode. The single-point transmission modemeans that one transmission point independently completes datatransmission with one terminal device, and the coordinated multipointtransmission/reception mode means that a plurality of transmissionpoints in separated geographic positions jointly complete datatransmission with one terminal device. A transmission point may beunderstood as a network device, or may be a base station, or may be aradio frequency unit of a base station, for example, a remote radio unit(RRU), or may be a panel of a base station or a transmission point, orthe like. One base station or one transmission point may include one ormore panels. Data transmission includes data sending and receiving.

In a long term evolution (LTE) communications system, in the prior art,one channel state information (CSI) process is configured for a scenarioin which one transmission mode is supported, and for the CSI process,the terminal device only needs to measure and feed back CSIcorresponding to the transmission mode. An enhanced CSI process isconfigured for a scenario in which a plurality of transmission modes aresupported, and for the enhanced CSI process, the terminal device needsto measure CSI in the plurality of transmission modes, and thenindicate, by feeding back the measured CSI to the network device, whichone of the single-point transmission mode and the coordinated multipointtransmission/reception mode has better performance. Processes ofmeasuring CSI by the terminal device and processes of feeding back themeasured CSI to the network device vary depending on transmission modes.However, in the prior art, the terminal device cannot determine whethera CSI process is an enhanced CSI process, to be specific, the terminaldevice cannot determine a specific transmission mode in which CSImeasurement and feedback need to be performed. Consequently, theterminal device cannot perform a CSI measurement process and a CSIfeedback process. In a fifth generation (5G) system, for the scenario inwhich a plurality of transmission modes are supported, no technicalsolution is currently available for the terminal device to perform CSImeasurement and feedback.

In conclusion, a technical solution for CSI measurement and feedback ina scenario in which a plurality of transmission modes are supported isurgently needed.

SUMMARY

Embodiments of the present disclosure provide a communications methodand device, to enable a terminal device to measure CSI and feed back themeasured CSI to a network device in a scenario in which a plurality oftransmission modes are supported.

According to a first aspect, an embodiment of the present disclosureprovides a communications method. In the method, a network device sendsconfiguration information to a terminal device; after receiving theconfiguration information, the terminal device determines channel stateinformation CSI measurement behavior and/or CSI feedback relatedinformation, where the channel state information CSI measurementbehavior and/or the CSI feedback related information are/is related tothe configuration information; and the terminal device performs CSImeasurement based on the configuration information and the CSImeasurement behavior and/or the CSI feedback related information, toobtain at least one piece of CSI, and sends all or some of the at leastone piece of CSI to the network device.

The CSI measurement behavior instructs the terminal device how tomeasure CSI, and the CSI feedback related information is relatedinformation used when the terminal device feeds back the CSI to thenetwork device. For example, the CSI feedback related information mayinclude at least one of the following information: content (for example,at least one of a CRI, an RI, a PMI, or a CQI) of the fed back CSI, bitinformation (for example, the bit information includes a bit widthand/or a rule for determining a bit width) of the content of the fedback CSI, a coding scheme (for example, independent encoding or jointencoding) used by the content of the fed back CSI, an interleaving mode(for example, independent interleaving or joint interleaving), and amapping mode (for example, a mapped time-frequency resource and/or amapping rule).

In the foregoing method, the network device determines a manner in whichthe terminal device is required to perform CSI measurement and feedback,to be specific, the network device determines a transmission mode inwhich the terminal device is required to perform CSI measurement andfeedback, and then the network device determines the configurationinformation based on the manner in which the terminal device is requiredto perform CSI measurement and feedback. The terminal device may learn,based on the configuration information, how to perform CSI measurementand feedback, where the configuration information is related to the CSImeasurement behavior and/or the CSI feedback related information.Therefore, according to the foregoing method, even if the terminaldevice cannot determine the transmission mode in which CSI measurementand feedback need to be performed, the terminal device may also learn,based on the configuration information sent by the network device, howto perform CSI measurement and/or feedback, so that in a scenario inwhich a plurality of transmission modes are supported, the terminaldevice measures CSI, and feeds back the measured CSI to the networkdevice. In the foregoing method, the terminal device and the networkdevice determine the CSI measurement behavior and/or the CSI feedbackrelated information based on the existing configuration information,thereby reducing signaling overheads. When a resource is configured inthe configuration information, the terminal device can perform CSImeasurement and feedback in the plurality of transmission modes.Compared with configuration of CSI measurement and feedback in onetransmission mode once, signaling overheads can be reduced, referencesignal overheads can be reduced, a delay of CSI measurement and feedbackcan be reduced, and performance can be improved. If the terminal devicefeeds back only CSI in a transmission mode with optimal transmissionperformance, feedback overheads can be reduced, and the network deviceis assisted in performing data scheduling based on the optimaltransmission mode. Alternatively, if the terminal device can feed backCSI in the plurality of transmission modes, the network device mayobtain transmission performance statuses in the plurality oftransmission modes, to assist data scheduling and improve performance.

In a design, the network device determines the CSI measurement behaviorand/or the CSI feedback related information of the terminal device, andthen receives the CSI from the terminal device based on the CSImeasurement behavior and/or the CSI feedback related information.

In the foregoing method, the network device receives the CSI from theterminal device by using a method corresponding to a method forperforming CSI measurement and feedback by the terminal device. To bespecific, the network device receives the CSI from the terminal devicebased on the CSI measurement behavior and/or the CSI feedback relatedinformation. It should be noted that, when the network device learns ofthe method for performing CSI measurement and feedback by the terminaldevice, a method for receiving the CSI by the network device may be thesame as that in the prior art.

In a design, based on the fact that the network device determines thatthe terminal device is required to perform CSI measurement and feedbackin a hybrid mode (which may also be referred to as a hybrid transmissionmode) of a single-point transmission mode+a coordinated multipointtransmission/reception mode, the configuration information and thechannel state information CSI measurement behavior and/or the CSIfeedback related information are as follows:

The configuration information meets at least one of the followingconditions:

-   -   (1) The configuration information includes N1 non-zero power        channel state information-reference signal NZP CSI-RS resources        of a class A, where N1 is a positive integer greater than or        equal to 2.

In an LTE communications system, that the configuration informationincludes N1 NZP CSI-RS resources of a class A means that theconfiguration information includes configuration information of one CSIprocess. In an NR communications system, that the configurationinformation includes N1 NZP CSI-RS resources of a class A may mean thatthe configuration information includes one CSI reporting setting(reporting setting), where the reporting setting is associated with Rpieces of association information (link) used for channel measurement,to be specific, associated with R reference signal settings (RSsetting), each RS setting includes at least one NZP CSI-RS resource ofthe class A, and the R RS settings include the N1 NZP CSI-RS resourcesof the class A; or the configuration information includes one reportingsetting, where the reporting setting is associated with one piece ofassociation information, namely, a link, used for channel measurement,to be specific, associated with one RS setting, and the RS settingincludes the N1 NZP CSI-RS resources of the class A.

-   -   (2) The configuration information includes N2 NZP CSI-RS        resources of a class B and CSI measurement behavior indication        information and/or CSI feedback related information indication        information, where N2 is a positive integer greater than or        equal to 2, the CSI measurement behavior indication information        indicates the CSI measurement behavior, and the CSI feedback        related information indication information indicates the CSI        feedback related information.    -   (3) The configuration information includes CSI measurement        behavior indication information and/or CSI feedback related        information indication information.

In the foregoing conditions (2) and (3), the CSI measurement behaviorindication information indicates the CSI measurement behavior, and theCSI measurement behavior is behavior of performing CSI measurement bythe terminal device in the hybrid mode; and the CSI feedback relatedinformation indication information indicates the CSI feedback relatedinformation, and the CSI feedback related information is relatedinformation used when the terminal device feeds back the CSI in thehybrid mode. Information related to the behavior of performing CSImeasurement by the terminal device in the hybrid mode and the relatedinformation used when the terminal device feeds back the CSI in thehybrid mode are described below.

The terminal device and the network device may directly determine theCSI measurement behavior and/or the CSI feedback related informationbased on the configuration information that meets the condition (3), sothat the terminal device does not need to perform determining andselection, thereby reducing complexity of the terminal device.

-   -   (4) The configuration information includes a quasi-co-location        (QCL) type of an antenna port that is a type C.

In one embodiment, when the QCL type is the type C, the CSI measurementbehavior and/or the CSI feedback related information may alternativelybe determined with reference to another condition, for example, at leastone condition in (1) to (12) or another condition. This is notspecifically limited herein.

-   -   (5) The configuration information includes a QCL type of an        antenna port that is a type C and a CSI process quantity that is        1.

The condition (5) is applicable to the LTE communications system. Whenthe configuration information meets the condition (5), it may bedetermined that the network device requires the terminal device toperform CSI measurement and feedback in the hybrid mode.

-   -   (6) The configuration information includes a physical downlink        shared channel mapping and quasi-co-location indicator PQI that        indicates that a QCL quantity is greater than M, where M is a        positive integer greater than or equal to 1.    -   (7) The configuration information includes a PQI that indicates        that a parameter group quantity is greater than P, where P is a        positive integer greater than or equal to 1.    -   (8) The configuration information includes at least one of bit        information for CSI-reference signal resource indicator, CRI,        reporting, bit information for CRI and RI reporting, and bit        information for RI reporting.

If at least one of bit information for CRI reporting, bit informationfor CRI and RI reporting, and bit information for RI reporting that areused when the network device requires the terminal device to perform CSImeasurement and feedback in the single-point transmission mode may be apredefined value, the configuration information does not need to includeat least one of the bit information for CRI reporting, the bitinformation for CRI and RI reporting, and the bit information for RIreporting, so that when the configuration information meets thecondition (8), it may be determined that the network device requires theterminal device to perform CSI measurement and feedback in the hybridmode. If one or more of the bit information for CRI reporting, the bitinformation for CRI and RI reporting, and the bit information for RIreporting that are used when the network device requires the terminaldevice to perform CSI measurement and feedback in the single-pointtransmission mode are also configured by using the configurationinformation, when the configuration information meets the condition (8),it is further determined, with reference to other information in theconfiguration information, that the network device requires the terminaldevice to perform CSI measurement and feedback in the hybrid mode.

-   -   (9) The configuration information includes that when bit        information for CRI reporting is L and there are K NZP CSI-RS        resources, L≠┌log₂K┐.

In one embodiment, the NZP CSI-RS resource may be a resource for channelmeasurement, a resource for interference measurement, a resource forboth channel measurement and interference measurement, or a totalresource including a resource for channel measurement and a resource forinterference measurement. This is not specifically limited herein.

When the configuration information meets the condition (9), it may bedetermined that the network device requires the terminal device toperform CSI measurement and feedback in the hybrid mode. The bitinformation for CRI reporting may be configured by using higher layersignaling or physical layer signaling. The higher layer signaling may beRRC signaling or MAC layer signaling. This is not specifically limitedherein.

-   -   (10) The configuration information includes one CSI reporting        setting reporting setting, where the reporting setting is        associated with at least one of Q channel links, T reference        signal settings RS settings, and S reference signal sets RS        sets, where Q is a positive integer greater than or equal to 2,        T is a positive integer greater than or equal to 2, and S is a        positive integer greater than or equal to 2.    -   (11) The configuration information includes a first resource and        a second resource, where the first resource is a resource used        to measure at least one of first CSI, second CSI, and third CSI,        and the second resource is a resource used to measure fourth        CSI.

The first CSI is obtained based on interference power; the second CSI isobtained based on interference that is obtained by using a presetalgorithm when a resource used for channel measurement is the same as aresource used for interference measurement; the third CSI is obtainedbased on interference power and interference that is obtained by using apreset algorithm when a resource used for channel measurement is thesame as a resource used for interference measurement; the presetalgorithm may be that interference is equal to a difference between areceived signal and a wanted signal; and the fourth CSI is obtainedbased on inter-stream interference or inter-codeword interference.

Measurement of at least one of the first CSI, the second CSI, and thethird CSI indicates that the terminal device needs to perform CSImeasurement and feedback in the single-point transmission mode, andmeasurement of the fourth CSI indicates that the terminal device needsto perform CSI measurement and feedback in the coordinated multipointtransmission/reception mode. Therefore, when the configurationinformation includes the first resource and the second resource, itindicates that the terminal device needs to perform CSI measurement andfeedback in the hybrid mode.

-   -   (12) The configuration information includes second indication        information, where the second indication information instructs        the terminal device to perform CSI measurement and feedback in        the hybrid transmission mode. The second indication information        indicates that a current CSI process is a CSI process in the        coordinated multipoint transmission/reception mode, and the        terminal device learns, based on the indication information, to        perform CSI measurement and feedback in the hybrid transmission        mode.

In one embodiment, the second indication information may be signaling.For example, in the LTE communications system, the second indicationinformation is an NCJT CSI process indication, and when higher layersignaling CoMP-Process=TRUE, it indicates that a current CSI process isa CSI process in the coordinated multipoint transmission/reception mode,so that the terminal device is instructed to perform CSI measurement andfeedback in the hybrid transmission mode. For another example, in the NRcommunications system, when higher layer signaling CoMP-Process=TRUE, itindicates that the terminal device performs CSI measurement and feedbackin the hybrid transmission mode. The higher layer signaling may beincluded in a measurement configuration MeasConfig, or may be includedin a reporting configuration ReportConfig.

In one embodiment, the second indication information may indicate afirst resource and a second resource, the first resource is a resourceused to measure at least one of first CSI, second CSI, and third CSI,and the second resource is a resource used to measure fourth CSI.

When the configuration information meets at least one of the foregoingconditions (1) to (12), related CSI measurement behavior and/or CSIfeedback related information is as follows:

The CSI measurement behavior includes measurement of at least one of thefirst CSI, the second CSI, and the third CSI, and measurement of thefourth CSI; and/or

the CSI feedback related information includes use of joint encoding orindependent encoding for channel state information-reference signalresource indicator CRI and a rank indicator RI, and/or a mapping mode ofmapping a CRI and an RI to a time-frequency resource. The use of jointencoding or independent encoding for the CRI and the RI means that theCRI and the RI are jointly encoded or separately encoded. Whether jointencoding is performed on other information and the CRI and/or the RI isnot limited.

In a design, the CSI measurement behavior indication informationinstructs to measure at least one of the first CSI, the second CSI, andthe third CSI, and instructs to measure the fourth CSI.

In this way, the terminal device may directly determine the CSImeasurement behavior based on the configuration information, so that theterminal device does not need to perform determining and selection,thereby reducing complexity of the terminal device.

In a design, the CSI feedback related information indication informationindicates use of joint encoding for the CRI and the RI, or indicates useof independent encoding for the CRI and the RI; and/or

the CSI feedback related information indication information indicatesthe mapping mode of mapping the CRI and the RI to the time-frequencyresource.

In this way, the terminal device may directly determine the CSI feedbackrelated information based on the configuration information, so that theterminal device does not need to perform determining and selection,thereby reducing complexity of the terminal device.

In a design, the fourth CSI is further obtained based on interferencepower; or the fourth CSI is further obtained based on interference thatis obtained by using a preset algorithm when a resource used for channelmeasurement is the same as a resource used for interference measurement;or the fourth CSI is further obtained based on interference power andinterference that is obtained by using a preset algorithm when aresource used for channel measurement is the same as a resource used forinterference measurement.

In a design, the CSI feedback related information further includes atleast one of the bit information for CRI reporting, the bit informationfor CRI and RI reporting, and the bit information for RI reporting; andat least one of the bit information for CRI reporting, the bitinformation for CRI and RI reporting, and the bit information for RIreporting may be determined in the following manner:

-   -   Preset rule 1: At least one of the bit information for CRI        reporting, the bit information for CRI and RI reporting, and the        bit information for RI reporting is determined based on a        maximum bit width of the CRI and the RI.    -   Preset rule 2: At least one of the bit information for CRI        reporting, the bit information for CRI and RI reporting, and the        bit information for RI reporting is determined in consideration        of both the CRI and the RI.    -   Preset rule 3: In the NR communications system, at least one of        the bit information for CRI reporting, the bit information for        CRI and RI reporting, and the bit information for RI reporting        may be determined based on a quantity of links or a quantity of        measurement channels.

In a design, the configuration information includes second indicationinformation, where the second indication information instructs theterminal device to perform CSI measurement and feedback in the hybridtransmission mode, or indicates that a current CSI process is a CSIprocess in the coordinated multipoint transmission/reception mode; andthe terminal device may determine the CSI feedback related informationbased on the second indication information, where the CSI feedbackrelated information includes at least one of a coding scheme for a CRIand an RI, a bit width of a CRI, a bit width of an RI, a bit meaning ofa CRI, or a bit meaning of an RI. For the network device, the CSIfeedback related information includes at least one of the coding schemefor the CRI and the RI, the bit width of the CRI, the bit width of theRI, the bit meaning of the CRI, or the bit meaning of the RI, and thatthe configuration information is related to the CSI measurement behaviorand/or the CSI feedback related information includes: at least one ofthe coding scheme for the CRI and the RI, the bit width of the CRI, thebit width of the RI, the bit meaning of the CRI, or the bit meaning ofthe RI is related to the second indication information.

In the foregoing method, the network device determines a transmissionmode in which the terminal device is required to perform CSI measurementand feedback, and then the network device determines the secondindication information based on the transmission mode in which theterminal device is required to perform CSI measurement and feedback. Theterminal device may learn, based on the second indication information,of the transmission mode in which CSI measurement and feedback areperformed, where the second indication information is related to atleast one of the coding scheme for the CRI and the RI, the bit width ofthe CRI, the bit width of the RI, the bit meaning of the CRI, or the bitmeaning of the RI. Therefore, according to the foregoing method, even ifthe terminal device cannot determine the transmission mode in which CSImeasurement and feedback need to be performed, the terminal device mayalso learn, based on the second indication information sent by thenetwork device, of the transmission mode in which CSI measurement and/orfeedback are/is performed, so that in a scenario in which a plurality oftransmission modes are supported, the terminal device measures CSI, andfeeds back the measured CSI to the network device.

In a design, the determined coding scheme for the CRI and the RI is: useof joint encoding or independent encoding for the CRI and the RI.

In a design, the determining the CSI feedback related information basedon the second indication information includes: determining at least oneof the bit width of the CRI, the bit width of the RI, the bit meaning ofthe CRI, or the bit meaning of the RI based on the second indicationinformation; or determining at least one of the bit width of the CRI orthe bit width of the RI based on the second indication information andat least one of a quantity of NZP CSI-RS resources, a quantity ofantenna ports for an NZP CSI-RS, capability information of the terminaldevice, or a value of the CRI; or determining at least one of the bitmeaning of the CRI or the bit meaning of the RI based on the secondindication information and at least one of a quantity of NZP CSI-RSresources, a quantity of antenna ports for an NZP CSI-RS, capabilityinformation of the terminal device, the bit width of the RI, or a valueof the CRI. Correspondingly, that at least one of the coding scheme forthe CRI and the RI, the bit width of the CRI, the bit width of the RI,the bit meaning of the CRI, or the bit meaning of the RI is related tothe second indication information includes: at least one of the bitwidth of the CRI, the bit width of the RI, the bit meaning of the CRI,or the bit meaning of the RI is related to the second indicationinformation; or at least one of the bit width of the CRI or the bitwidth of the RI is related to the second indication information and atleast one of the quantity of NZP CSI-RS resources, the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the value of the CRI; or at least one of the bitmeaning of the CRI or the bit meaning of the RI is related to the secondindication information and at least one of the quantity of NZP CSI-RSresources, the quantity of antenna ports for an NZP CSI-RS, thecapability information of the terminal device, the bit width of the RI,or the value of the CRI.

In this embodiment of the present disclosure, the CSI feedback relatedinformation may be determined in a plurality of different manners. Thisis relatively flexible.

In a design, the determining at least one of the bit width of the CRI,the bit width of the RI, the bit meaning of the CRI, or the bit meaningof the RI based on the second indication information includes at leastone of the following cases: determining the bit width of the CRI and/orthe bit width of the RI based on the second indication information; ordetermining the bit meaning of the CRI and/or the bit meaning of the RIbased on the second indication information. Correspondingly, that atleast one of the bit width of the CRI, the bit width of the RI, the bitmeaning of the CRI, or the bit meaning of the RI is related to thesecond indication information includes at least one of the followingcases: the bit width of the CRI and/or the bit width of the RI are/isrelated to the second indication information; or the bit meaning of theCRI and/or the bit meaning of the RI are/is related to the secondindication information.

In this manner, when the RI and the CRI are jointly fed back or jointlyencoded, the bit width of the RI is enabled to be independent of thevalue of the CRI, to be specific, it can be ensured that the bit widthof the CRI and the bit width of the RI are fixed, so that the networkdevice can correctly and jointly receive or jointly decode the CRI andthe RI.

In a design, the determining at least one of the bit width of the CRI orthe bit width of the RI based on the second indication information andat least one of a quantity of NZP CSI-RS resources, a quantity ofantenna ports for an NZP CSI-RS, capability information of the terminaldevice, or a value of the CRI includes at least one of the followingcases: determining the bit width of the CRI based on the quantity of NZPCSI-RS resources and the second indication information; or determiningthe bit width of the RI based on the second indication information andthe quantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or determining the bit width of theRI based on the second indication information, the value of the CRI, andthe quantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or determining the bit width of theRI based on the second indication information and the value of the CRI.Correspondingly, that at least one of the bit width of the CRI or thebit width of the RI is related to the second indication information andat least one of the quantity of NZP CSI-RS resources, the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the value of the CRI includes at least one of thefollowing cases: the bit width of the CRI is related to the quantity ofNZP CSI-RS resources and the second indication information; or the bitwidth of the RI is related to the second indication information and thequantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or the bit width of the RI isrelated to the second indication information, the value of the CRI, andthe quantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or the bit width of the RI isrelated to the second indication information and the value of the CRI.

In this embodiment of the present disclosure, at least one of the bitwidth of the CRI and the bit width of the RI may be determined in aplurality of different manners. This is relatively flexible.

According to the foregoing method, when the RI and the CRI are jointlyfed back or jointly encoded, the bit width of the RI is enabled to beindependent of the value of the CRI, to be specific, it can be ensuredthat the bit width of the CRI and the bit width of the RI are known byboth the network device and the terminal device, so that the networkdevice can correctly and jointly receive or jointly decode the CRI andthe RI. In addition, because the bit width of the RI is related to thequantity of antenna ports and/or a capability of the terminal device,overheads for the bit width of the RI are relatively low.

In a design, the determining at least one of the bit meaning of the CRIor the bit meaning of the RI based on the second indication informationand at least one of a quantity of NZP CSI-RS resources, a quantity ofantenna ports for an NZP CSI-RS, capability information of the terminaldevice, the bit width of the RI, or a value of the CRI includes at leastone of the following cases: determining the bit meaning of the CRI basedon the second indication information and the value of the CRI; ordetermining the bit meaning of the RI based on the value of the CRI, thesecond indication information, and at least one of the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the bit width of the RI; or determining the bitmeaning of the RI based on the second indication information and the bitwidth of the RI; or determining the bit meaning of the RI based on thesecond indication information and the value of the CRI; or determiningthe bit meaning of the CRI based on the second indication informationand the quantity of NZP CSI-RS resources. Correspondingly, that at leastone of the bit meaning of the CRI or the bit meaning of the RI isrelated to the second indication information and at least one of thequantity of NZP CSI-RS resources, the quantity of antenna ports for anNZP CSI-RS, the capability information of the terminal device, the bitwidth of the RI, or the value of the CRI includes at least one of thefollowing cases: the bit meaning of the RI is related to the secondindication information and the value of the CRI; or the bit meaning ofthe RI is related to the value of the CRI, the second indicationinformation and at least one of the quantity of antenna ports for an NZPCSI-RS, the capability information of the terminal device, or the bitwidth of the RI; or the bit meaning of the RI is related to the secondindication information and the bit width of the RI; or the bit meaningof the RI is related to the second indication information and the valueof the CRI; or the bit meaning of the CRI is related to the secondindication information and a quantity of NZP CSI-RS resources.

In a design, the terminal device determines, based on the secondindication information, to feed back at least two CSI sets, where the atleast two CSI sets include a first set of CSI and a second set of CSI; afeedback sequence of the at least two CSI sets includes one of thefollowing cases: a CQI of the first set and a CQI of the second set aresequentially fed back; or a CQI of the first set, a CQI of the secondset, and a PMI of the first set are sequentially fed back; or a CQI ofthe first set, a CQI of the second set, a PMI of the first set, and aPMI of the second set are sequentially fed back; or a CQI of the firstset, a PMI of the first set, and a CQI of the second set aresequentially fed back; or a CQI of the first set, a CQI of the secondset, and a PMI of the second set are sequentially fed back; or a CQI ofthe first set, a PMI of the first set, a CQI of the second set, and aPMI of the second set are sequentially fed back; and the first set ofCSI corresponds to CSI for the first NZP CSI-RS resource, and the secondset of CSI corresponds to CSI for the second NZP CSI-RS resource; or thefirst set of CSI corresponds to CSI for the first codeword, and thesecond set of CSI corresponds to CSI for the second codeword.Correspondingly, the network device determines that the at least two CSIsets fed back by the terminal device are related to the secondindication information, where the at least two CSI sets include thefirst set of CSI and the second set of CSI; the feedback sequence of theat least two CSI sets includes one of the following cases: the CQI ofthe first set and the CQI of the second set are sequentially fed back;or the CQI of the first set, the CQI of the second set, and the PMI ofthe first set are sequentially fed back; or the CQI of the first set,the CQI of the second set, the PMI of the first set, and the PMI of thesecond set are sequentially fed back; or the CQI of the first set, thePMI of the first set, and the CQI of the second set are sequentially fedback; or the CQI of the first set, the CQI of the second set, and thePMI of the second set are sequentially fed back; or the CQI of the firstset, the PMI of the first set, the CQI of the second set, and the PMI ofthe second set are sequentially fed back; and the first set of CSIcorresponds to the CSI for the first NZP CSI-RS resource, and the secondset of CSI corresponds to the CSI for the second NZP CSI-RS resource; orthe first set of CSI corresponds to the CSI for the first codeword, andthe second set of CSI corresponds to the CSI for the second codeword.

If there are the at least two CSI sets, there may be a plurality offeedback sequences of the at least two CSI sets, and a specific feedbacksequence to be used may be specified by the network device in advance,or specified in a protocol.

In a design, the terminal device further sends third indicationinformation to the network device, where the third indicationinformation indicates a QCL type supported by the terminal device, orindicates that FeCoMP-based CSI measurement and/or feedback are/issupported. Correspondingly, the network device receives the thirdindication information from the terminal device, where the thirdindication information indicates the QCL type supported by the terminaldevice, or indicates that FeCoMP-based CSI measurement and/or feedbackare/is supported.

The CSI measurement behavior in this embodiment of the presentdisclosure includes FeCoMP-based CSI measurement. A FeCoMP feature isintroduced to the protocol release R15. In this case, for terminaldevices supporting the protocol release R15, because of differentcapabilities of the terminal devices, some terminal devices may notsupport FeCoMP due to limitations of capabilities such as hardwarestorage or processing capabilities, and some terminal devices have astrong capability and can support FeCoMP. Therefore, this embodiment ofthe present disclosure provides a solution: When accessing a network,the terminal device may report, by using the third indicationinformation, whether FeCoMP-based CSI measurement is supported, as acapability of the terminal device to the network device, so that thenetwork device can learn whether the terminal device supportsFeCoMP-based CSI measurement. The third indication information mayfurther indicate the QCL type supported by the terminal device, forexample, whether a QCL type C is supported.

According to a second aspect, an embodiment of the present disclosureprovides a communications apparatus. The communications apparatus has afunction of implementing the method according to the first aspect. Thefunction of the communications apparatus may be implemented by hardware,or may be implemented by hardware executing corresponding software. Thehardware or the software includes one or more modules corresponding tothe foregoing function. A device corresponding to the communicationsapparatus may be a terminal device or a network device.

In a design, when the device corresponding to the communicationsapparatus is the terminal device, the communications apparatus includesa processing unit and a transceiver unit. The processing unit isconfigured to support the terminal device in performing a correspondingfunction in the foregoing method. The transceiver unit is configured tosupport communication between the terminal device and another device(including a network device). The terminal device may further include astorage unit. The storage unit is configured to couple to the processingunit, and stores a program instruction and data that are suitable forthe terminal device.

In another design, when the device corresponding to the communicationsapparatus may be the terminal device, the communications apparatusincludes a memory, a processor, and an input/output port. The memory isconfigured to store a computer-readable program. The processor invokesan instruction stored in the memory, to perform the foregoing methodperformed by the terminal device according to the first aspect. Theinput/output port is configured to perform receiving and/or sendingunder control of the processor.

In another design, when the device corresponding to the communicationsapparatus is the network device, the communications apparatus includes aprocessing unit and a transceiver unit. The processing unit isconfigured to support the network device in performing a correspondingfunction in the foregoing method. The transceiver unit is configured tosupport communication between the network device and another device(including a terminal device). The network device may further include astorage unit. The storage unit is coupled to the processing unit, andstores a program instruction and data that are suitable for the networkdevice.

In another design, when the device corresponding to the communicationsapparatus is the network device, the communications apparatus includes amemory, a processor, and an input/output port. The memory is configuredto store a computer-readable program. The processor is configured toinvoke the instruction stored in the memory, to perform the foregoingmethod performed by the network device according to the first aspect.The input/output port is configured to perform receiving and/or sendingunder control of the processor.

For example, the processing unit may be a processor, the transceiverunit may be an input/output port, and the storage unit may be a memory.The input/output port may be a plurality of elements, that is, includesa transmitter and a receiver, or includes a communications interface.The communications interface has receiving and sending functions.

According to a third aspect, an embodiment of the present disclosurefurther provides a computer storage medium. The storage medium stores asoftware program or instruction, and when being read and executed by oneor more processors, the software program or instruction can implementthe communications method according to the first aspect.

According to a fourth aspect, an embodiment of the present disclosurefurther provides a computer program product including an instruction.When the computer program product is run on a computer, the computer isenabled to perform the communications method according to the firstaspect.

According to a fifth aspect, an embodiment of the present disclosurefurther provides a communications system. The communications systemincludes a terminal device and a network device.

According to a sixth aspect, an embodiment of the present disclosurefurther provides a communications method. In the communications method,a network device sends first indication information to a terminaldevice; the network device determines CSI feedback related information,and receives CSI feedback from the terminal device based on the CSIfeedback related information, where the CSI feedback related informationis related to the first indication information; the terminal device maydetermine the CSI feedback related information based on the firstindication information, where the CSI feedback related informationincludes at least one of a coding scheme for a CRI and an RI, a bitwidth of a CRI, a bit width of an RI, a bit meaning of a CRI, or a bitmeaning of an RI, and the first indication information is used to enableFeCoMP-based CSI feedback, or enable coordinated multipointtransmission/reception-based CSI feedback, or enable CSI feedback in ahybrid transmission mode.

In the foregoing method, the network device determines a transmissionmode in which the terminal device is required to perform CSI measurementand feedback, and then the network device determines the firstindication information based on the transmission mode in which theterminal device is required to perform CSI measurement and feedback. Theterminal device may learn, based on the first indication information, ofthe transmission mode in which CSI measurement and feedback areperformed, where the first indication information is related to at leastone of the coding scheme for the CRI and the RI, the bit width of theCRI, the bit width of the RI, the bit meaning of the CRI, or the bitmeaning of the RI. Therefore, according to the foregoing method, even ifthe terminal device cannot determine the transmission mode in which CSImeasurement and feedback need to be performed, the terminal device mayalso learn, based on the first indication information sent by thenetwork device, of the transmission mode in which CSI measurement and/orfeedback are/is performed, so that in a scenario in which a plurality oftransmission modes are supported, the terminal device measures CSI, andfeeds back the measured CSI to the network device.

In a design, the determined coding scheme for the CRI and the RI is: useof joint encoding or independent encoding for the CRI and the RI.

In a design, the determining the CSI feedback related information basedon the first indication information includes: determining at least oneof the bit width of the CRI, the bit width of the RI, the bit meaning ofthe CRI, or the bit meaning of the RI based on the first indicationinformation; or determining at least one of the bit width of the CRI orthe bit width of the RI based on the first indication information and atleast one of a quantity of NZP CSI-RS resources, a quantity of antennaports for an NZP CSI-RS, capability information of the terminal device,or a value of the CRI; or determining at least one of the bit meaning ofthe CRI or the bit meaning of the RI based on the first indicationinformation and at least one of a quantity of NZP CSI-RS resources, aquantity of antenna ports for an NZP CSI-RS, capability information ofthe terminal device, the bit width of the RI, or a value of the CRI.Correspondingly, that at least one of the coding scheme for the CRI andthe RI, the bit width of the CRI, the bit width of the RI, the bitmeaning of the CRI, or the bit meaning of the RI is related to the firstindication information includes: at least one of the bit width of theCRI, the bit width of the RI, the bit meaning of the CRI, or the bitmeaning of the RI is related to the first indication information; or atleast one of the bit width of the CRI or the bit width of the RI isrelated to the first indication information and at least one of thequantity of NZP CSI-RS resources, the quantity of antenna ports for anNZP CSI-RS, the capability information of the terminal device, or thevalue of the CRI; or at least one of the bit meaning of the CRI or thebit meaning of the RI is related to the first indication information andat least one of the quantity of NZP CSI-RS resources, the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, the bit width of the RI, or the value of the CRI.

In this embodiment of the present disclosure, the CSI feedback relatedinformation may be determined in a plurality of different manners. Thisis relatively flexible.

In a design, the determining at least one of the bit width of the CRI,the bit width of the RI, the bit meaning of the CRI, or the bit meaningof the RI based on the first indication information includes at leastone of the following cases: determining the bit width of the CRI and/orthe bit width of the RI based on the first indication information; ordetermining the bit meaning of the CRI and/or the bit meaning of the RIbased on the first indication information. Correspondingly, that atleast one of the bit width of the CRI, the bit width of the RI, the bitmeaning of the CRI, or the bit meaning of the RI is related to the firstindication information includes at least one of the following cases: thebit width of the CRI and/or the bit width of the RI are/is related tothe first indication information; or the bit meaning of the CRI and/orthe bit meaning of the RI are/is related to the first indicationinformation.

In this manner, when the RI and the CRI are jointly fed back or jointlyencoded, the bit width of the RI is enabled to be independent of thevalue of the CRI, to be specific, it can be ensured that the bit widthof the CRI and the bit width of the RI are fixed, so that the networkdevice can correctly and jointly receive or jointly decode the CRI andthe RI.

In a design, the determining at least one of the bit width of the CRI orthe bit width of the RI based on the first indication information and atleast one of a quantity of NZP CSI-RS resources, a quantity of antennaports for an NZP CSI-RS, capability information of the terminal device,or a value of the CRI includes at least one of the following cases:determining the bit width of the CRI based on the quantity of NZP CSI-RSresources and the first indication information; or determining the bitwidth of the RI based on the first indication information and thequantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or determining the bit width of theRI based on the first indication information, the value of the CRI, andthe quantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or determining the bit width of theRI based on the first indication information and the value of the CRI.Correspondingly, that at least one of the bit width of the CRI or thebit width of the RI is related to the first indication information andat least one of the quantity of NZP CSI-RS resources, the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the value of the CRI includes at least one of thefollowing cases: the bit width of the CRI is related to the quantity ofNZP CSI-RS resources and the first indication information; or the bitwidth of the RI is related to the first indication information and thequantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or the bit width of the RI isrelated to the first indication information, the value of the CRI, andthe quantity of antenna ports for an NZP CSI-RS and/or the capabilityinformation of the terminal device; or the bit width of the RI isrelated to the first indication information and the value of the CRI.

In this embodiment of the present disclosure, at least one of the bitwidth of the CRI and the bit width of the RI may be determined in aplurality of different manners. This is relatively flexible.

According to the foregoing method, when the RI and the CRI are jointlyfed back or jointly encoded, the bit width of the RI is enabled to beindependent of the value of the CRI, to be specific, it can be ensuredthat the bit width of the CRI and the bit width of the RI are known byboth the network device and the terminal device, so that the networkdevice can correctly and jointly receive or jointly decode the CRI andthe RI. In addition, because the bit width of the RI is related to thequantity of antenna ports and/or a capability of the terminal device,overheads for the bit width of the RI are relatively low.

In a design, the determining at least one of the bit meaning of the CRIor the bit meaning of the RI based on the first indication informationand at least one of a quantity of NZP CSI-RS resources, a quantity ofantenna ports for an NZP CSI-RS, capability information of the terminaldevice, the bit width of the RI, or a value of the CRI includes at leastone of the following cases: determining the bit meaning of the CRI basedon the first indication information and the value of the CRI; ordetermining the bit meaning of the RI based on the value of the CRI, thefirst indication information, and at least one of the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the bit width of the RI; or determining the bitmeaning of the RI based on the first indication information and the bitwidth of the RI; or determining the bit meaning of the RI based on thefirst indication information and the value of the CRI; or determiningthe bit meaning of the CRI based on the first indication information andthe quantity of NZP CSI-RS resources. Correspondingly, that at least oneof the bit meaning of the CRI or the bit meaning of the RI is related tothe first indication information and at least one of the quantity of NZPCSI-RS resources, the quantity of antenna ports for an NZP CSI-RS, thecapability information of the terminal device, the bit width of the RI,or the value of the CRI includes at least one of the following cases:the bit meaning of the RI is related to the first indication informationand the value of the CRI; or the bit meaning of the RI is related to thevalue of the CRI, the first indication information, and at least one ofthe quantity of antenna ports for an NZP CSI-RS, the capabilityinformation of the terminal device, or the bit width of the RI; or thebit meaning of the RI is related to the first indication information andthe bit width of the RI; or the bit meaning of the CRI is related to thefirst indication information and the value of the CRI; or the bitmeaning of the CRI is related to the first indication information andthe quantity of NZP CSI-RS resources.

In a design, the terminal device determines, based on the firstindication information, to feed back at least two CSI sets, where the atleast two CSI sets include a first set of CSI and a second set of CSI; afeedback sequence of the at least two CSI sets includes one of thefollowing cases: a CQI of the first set and a CQI of the second set aresequentially fed back; or a CQI of the first set, a CQI of the secondset, and a PMI of the first set are sequentially fed back; or a CQI ofthe first set, a CQI of the second set, a PMI of the first set, and aPMI of the second set are sequentially fed back; or a CQI of the firstset, a PMI of the first set, and a CQI of the second set aresequentially fed back; or a CQI of the first set, a CQI of the secondset, and a PMI of the second set are sequentially fed back; or a CQI ofthe first set, a PMI of the first set, a CQI of the second set, and aPMI of the second set are sequentially fed back; and the first set ofCSI corresponds to CSI for the first NZP CSI-RS resource, and the secondset of CSI corresponds to CSI for the second NZP CSI-RS resource; or thefirst set of CSI corresponds to CSI for the first codeword, and thesecond set of CSI corresponds to CSI for the second codeword.Correspondingly, the network device determines that the at least two CSIsets fed back by the terminal device are related to the first indicationinformation, where the at least two CSI sets include the first set ofCSI and the second set of CSI; the feedback sequence of the at least twoCSI sets includes one of the following cases: the CQI of the first setand the CQI of the second set are sequentially fed back; or the CQI ofthe first set, the CQI of the second set, and the PMI of the first setare sequentially fed back; or the CQI of the first set, the CQI of thesecond set, the PMI of the first set, and the PMI of the second set aresequentially fed back; or the CQI of the first set, the PMI of the firstset, and the CQI of the second set are sequentially fed back; or the CQIof the first set, the CQI of the second set, and the PMI of the secondset are sequentially fed back; or the CQI of the first set, the PMI ofthe first set, the CQI of the second set, and the PMI of the second setare sequentially fed back; and the first set of CSI corresponds to theCSI for the first NZP CSI-RS resource, and the second set of CSIcorresponds to the CSI for the second NZP CSI-RS resource; or the firstset of CSI corresponds to the CSI for the first codeword, and the secondset of CSI corresponds to the CSI for the second codeword.

If there are the at least two CSI sets, there may be a plurality offeedback sequences of the at least two CSI sets, and a specific feedbacksequence to be used may be specified by the network device in advance,or specified in a protocol.

In a design, the terminal device further sends third indicationinformation to the network device, where the third indicationinformation indicates that the terminal device supports FeCoMP-based CSImeasurement and/or feedback. Correspondingly, the network devicereceives the third indication information from the terminal device,where the third indication information indicates a QCL type supported bythe terminal device, or indicates that FeCoMP-based CSI measurementand/or feedback are/is supported.

The CSI measurement behavior in this embodiment of the presentdisclosure includes FeCoMP-based CSI measurement. A FeCoMP feature isintroduced to the protocol release R15. In this case, for terminaldevices supporting the protocol release R15, because of differentcapabilities of the terminal devices, some terminal devices may notsupport FeCoMP due to limitations of capabilities such as hardwarestorage or processing capabilities, and some terminal devices have astrong capability and can support FeCoMP. Therefore, this embodiment ofthe present disclosure provides a solution: When accessing a network,the terminal device may report, by using the third indicationinformation, whether FeCoMP-based CSI measurement is supported, as acapability of the terminal device to the network device, so that thenetwork device can learn whether the terminal device supportsFeCoMP-based CSI measurement. The third indication information mayfurther indicate the QCL type supported by the terminal device.

The first indication information according to the sixth aspect and thesecond indication information according to the first aspect may be sameindication information.

According to a seventh aspect, an embodiment of the present disclosureprovides a communications apparatus. The communications apparatus has afunction of implementing the method according to the sixth aspect. Thefunction of the communications apparatus may be implemented by hardware,or may be implemented by hardware executing corresponding software. Thehardware or the software includes one or more modules corresponding tothe foregoing function. A device corresponding to the communicationsapparatus may be a terminal device or a network device.

In a design, when the device corresponding to the communicationsapparatus is the terminal device or a chip that can be disposed in theterminal device, the communications apparatus includes a processing unitand a transceiver unit. The processing unit is configured to support theterminal device in performing a corresponding function in the foregoingmethod. The transceiver unit is configured to support communicationbetween the terminal device and another device (including a networkdevice). The terminal device may further include a storage unit. Thestorage unit is configured to couple to the processing unit, and storesa program instruction and/or data that are/is suitable for the terminaldevice.

In another design, when the device corresponding to the communicationsapparatus may be the terminal device, the communications apparatusincludes a memory, a processor, and an input/output port. The memory isconfigured to store a computer-readable program or an instruction. Theprocessor runs the program or the instruction stored in the memory, toperform the foregoing method performed by the terminal device accordingto the sixth aspect. The input/output port is configured to performreceiving and/or sending under control of the processor.

In another design, when the device corresponding to the communicationsapparatus is the network device, the communications apparatus includes aprocessing unit and a transceiver unit. The processing unit isconfigured to support the network device in performing a correspondingfunction in the foregoing method according to the sixth aspect. Thetransceiver unit is configured to support communication between thenetwork device and another device (including a terminal device). Thenetwork device may further include a storage unit. The storage unit isconfigured to couple to the processing unit, and stores a programinstruction and/or data that are/is suitable for the network device.

In another design, when the device corresponding to the communicationsapparatus is the network device or a chip that can be disposed in thenetwork device, the communications apparatus includes a memory, aprocessor, and an input/output port. The memory is configured to store acomputer-readable program or an instruction. The processor runs theprogram or the instruction stored in the memory, to perform theforegoing method performed by the network device according to the sixthaspect. The input/output port is configured to perform receiving and/orsending under control of the processor.

For example, the processing unit may be a processor, the transceiverunit may be an input/output port, and the storage unit may be a memory.The input/output port may include a transmitter and a receiver, orinclude a communications interface, for example, an input/output port ofthe chip. The communications interface has receiving and sendingfunctions.

According to an eighth aspect, an embodiment of the present disclosurefurther provides a computer storage medium. The storage medium stores asoftware program or instruction, and when being read and executed by oneor more processors, the software program or instruction can implementthe communications method according to the sixth aspect.

According to a ninth aspect, an embodiment of the present disclosurefurther provides a computer program product including an instruction.When the computer program product is run on a computer, the computer isenabled to perform the communications method according to the sixthaspect.

According to a tenth aspect, an embodiment of the present disclosurefurther provides a communications system. The communications systemincludes a terminal device and a network device.

In the technical solutions provided in the embodiments of the presentdisclosure, because the network device determines, based on a manner inwhich the terminal device is required to perform CSI measurement andfeedback, namely, a transmission mode in which the terminal device isrequired to perform CSI measurement and feedback, to send theconfiguration information to the terminal device, and the terminaldevice may learn, based on the configuration information, how to performCSI measurement and feedback. Therefore, in the technical solutions, theterminal device may learn, based on the configuration information sentby the network device, how to perform CSI measurement and/or feedback,so that in a scenario in which a plurality of transmission modes aresupported, the terminal device measures CSI, and feeds back the measuredCSI to the network device. In the technical solutions, the terminaldevice determines the CSI measurement behavior and/or the CSI feedbackrelated information based on the configuration information, therebyreducing signaling overheads. Further, when a corresponding resource isconfigured in the configuration information, the terminal device canperform CSI measurement and feedback in the plurality of transmissionmodes. Compared with configuration of CSI measurement and feedback inone transmission mode once, signaling overheads can be reduced,reference signal overheads can be reduced, a delay of CSI measurementand feedback can be reduced, and performance can be improved. Further,if the terminal device feeds back only CSI in a transmission mode withoptimal transmission performance, feedback overheads can be reduced, andthe network device is assisted in performing data scheduling based onthe optimal transmission mode. Alternatively, further, if the terminaldevice can feed back CSI in the plurality of transmission modes, thenetwork device may obtain transmission performance statuses in theplurality of transmission modes, to assist data scheduling and improveperformance.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a network architecture in a coordinatedmultipoint transmission/reception mode according to an embodiment of thepresent disclosure;

FIG. 2 is a schematic diagram of a network architecture in a coordinatedmultipoint multistream transmission/reception technology according to anembodiment of the present disclosure;

FIG. 3 is a schematic diagram of a network architecture of a 5G systemaccording to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a network architecture of a 5G systemaccording to an embodiment of the present disclosure;

FIG. 5-1 is a schematic flowchart of a communications method accordingto an embodiment of the present disclosure;

FIG. 5-2 is a schematic diagram of a resource configuration for CSIaccording to an embodiment of the present disclosure;

FIG. 5-3 is a schematic flowchart of a communications method accordingto an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of a first mapping mode according to anembodiment of the present disclosure;

FIG. 7 is a schematic diagram of a second mapping mode according to anembodiment of the present disclosure;

FIG. 8 is a schematic diagram of a third mapping mode according to anembodiment of the present disclosure;

FIG. 9 is a schematic diagram of a fourth mapping mode according to anembodiment of the present disclosure;

FIG. 10A is another schematic diagram of a resource configuration forCSI according to an embodiment of the present disclosure;

FIG. 10B is a schematic flowchart of a communications method accordingto an embodiment of the present disclosure;

FIG. 11 is a first schematic diagram of a device according to anembodiment of the present disclosure;

FIG. 12 is a schematic structural diagram of a terminal device accordingto an embodiment of the present disclosure;

FIG. 13 is a second schematic diagram of a device according to anembodiment of the present disclosure; and

FIG. 14 is a schematic structural diagram of a network device accordingto an embodiment of the present disclosure.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure provide a communications methodand device, to enable a terminal device to measure CSI and feed back themeasured CSI to a network device in a scenario in which a plurality oftransmission modes are supported. The method and the device are based ona same inventive idea. Because problem resolving principles of themethod and the device are similar, for implementation of the device andthe method, mutual reference may be made, and repeated parts are notdescribed in detail again.

The technical solutions provided in the embodiments of the presentdisclosure are applicable to a scenario in which transmission between aterminal device and a network device supports a plurality oftransmission modes, where the plurality of transmission modes mayinclude a single-point transmission mode and a coordinated multipointtransmission/reception mode. The single-point transmission mode meansthat data transmission between a single transmission point and a sameterminal device can be supported in one time unit, and the coordinatedmultipoint transmission/reception mode means that data transmissionbetween a plurality of transmission points and a same terminal devicecan be supported in one time unit. Data transmission includes datasending and receiving. A time unit may be a scheduling unit, and thescheduling unit may include at least one of one or more subframes, oneor more slots, one or more mini-slots, and one or more symbols. This maybe specifically determined based on system implementation or a protocol.In the embodiments of the present disclosure, the single-pointtransmission mode may be single-site transmission, dynamic pointselection (DPS) transmission, dynamic point blanking (DPB) transmission,or another single-point transmission manner. This is not specificallylimited herein. The coordinated multipoint transmission/reception modemay be coherent joint transmission (JT), non-coherent joint transmission(NCJT), or another joint transmission manner. This is not specificallylimited herein.

In the coordinated multipoint transmission/reception mode, atransmission point is a transmission point used for coordinatedtransmission, a transmission point used for coordinated transmission isa transmission point in a coordination set, and transmission points inthe coordination set jointly complete data transmission with a terminaldevice. Signals sent by any two transmission points in the coordinationset may be subject to different large-scale fading characteristics (thatis, non-quasi-co-location), and the two transmission points may belongto a same cell or different cells. This is not limited in theembodiments of the present disclosure. For a definition of QCL in theembodiments of the present disclosure, refer to a definition in LTE. Tobe specific, signals sent through QCL-ed antenna ports are subject tosame large-scale fading. The large-scale fading includes one or more ofthe following: a delay spread, a Doppler spread, a Doppler shift, anaverage channel gain, an average delay, and the like. In the embodimentsof the present disclosure, for the definition of the QCL, further referto a definition of the QCL in 5G. In a new radio NR system, a definitionof the QCL is similar to that in an LTE system, but space domaininformation is added. For example, signals sent from QCL-ed antennaports are subject to same large-scale fading. The large-scale fadingincludes one or more of the following parameters: a delay spread, aDoppler spread, a Doppler shift, an average channel gain, an averagedelay, a space domain parameter, and the like. The spatial domainparameter may be, for example, one of a radiation angle (AOA), adominant radiation angle (Dominant AoA), an average angle of arrival(Average AoA), an angle of arrival (AOD), a channel correlation matrix,a power angle spread spectrum of an angle of arrival, an average angleof departure (Average AoD), a power angle spread spectrum of an angle ofdeparture, a transmit channel correlation, a receive channelcorrelation, transmit beamforming, receive beamforming, a spatialchannel correlation, a filter, a spatial filtering parameter, or aspatial receiving parameter. For example, FIG. 1 is a schematic diagramof a network architecture in a coordinated multipointtransmission/reception mode. In FIG. 1 , a remote radio unit (RRU) isused as a transmission point, an RRU 1 and an RRU 2 jointly send data toa terminal device 1, the RRU 1 and the RRU 2 jointly receive data fromthe terminal device 1, and the RRU 1 and the RRU 2 perform coordinatedscheduling or coordinated beamforming. Further, in the coordinatedmultipoint transmission/reception mode, a coordinated multipointmultistream transmission/reception technology is used. By using thetechnology, different transmission points independently performprecoding, the different transmission points transmit different datastreams, different codewords, or different transport blocks. In thecoordinated multipoint transmission/reception mode, in addition to thecoordinated multipoint multistream transmission/reception technology,the different transmission points may alternatively transmit differentdata streams or same data streams/codewords/transport blocks, or thelike. The same data streams/codewords/transport blocks transmitted bythe different transmission points use different coding schemes, or thesame transmitted data streams/codewords/transport blocks use aredundancy version. This is not specifically limited herein. It shouldbe noted that, in the coordinated multipoint multistreamtransmission/reception technology, when channel quality indicator (CQI)of a data stream is calculated, an interference status of another datastream is considered. For example, FIG. 2 is a schematic diagram of anetwork architecture in a coordinated multipoint multistreamtransmission/reception technology. In FIG. 2 , transmission points 1 areused as an example. A plurality of transmission points including thetransmission points 1 jointly transmit data to a terminal device,different elliptical areas corresponding to the transmission points 1indicate that the transmission points 1 transmit different data streams.

The network device in the embodiments of the present disclosure may be adevice having a wireless receiving and sending function, and includes,but is not limited to, a base station, a relay station, an access point,a vehicle-mounted device, a wearable device, a network side device in afuture 5G network or a network device in a future evolved public landmobile network (PLMN), an access point in a Wi-Fi system, user equipment(UE), and the like. For example, the network device may be atransmission point (TRP or TP) in the NR system, a gNodeB (gNB) in theNR system, or one antenna panel or a group of antenna panels (includinga plurality of antenna panels) of a gNodeB in the 5G system. This is notparticularly limited in the embodiments of the present disclosure.

The terminal device in the embodiments of the present disclosure is adevice having a wireless receiving and sending function, and includes,but is not limited to, UE, an access terminal, a subscriber unit, asubscriber station, a mobile station, a mobile console, a remotestation, a remote terminal, a mobile device, a user terminal, aterminal, a wireless communications device, a user agent, or a userapparatus. The access terminal may be a cellular phone, a cordlessphone, a session initiation protocol (SIP) phone, a wireless local loop(WLL) station, a personal digital assistant (PDA), a handheld devicehaving a wireless communication function, a computing device, anotherprocessing device connected to a wireless modem, a vehicle-mounteddevice, a wearable device, an unmanned aerial vehicle device, a smartappliance, a terminal device in a future network, a terminal device in afuture evolved PLMN, or the like. This is not limited in the embodimentsof the present disclosure.

The technical solutions provided in the embodiments of the presentdisclosure may be applied to a new radio (NR) communications technology.NR is a new generation radio access network technology, and may beapplied to a future evolved network such as a 5G communications system.The technical solutions provided in the embodiments of the presentdisclosure may also be applied to wireless communications systems suchas LTE and wireless fidelity (WIFI).

It may be understood that the wireless communications system is anetwork that provides a wireless communication function. The wirelesscommunications system may use different communications technologies,such as code division multiple access (CDMA), wideband code divisionmultiple access (WCDMA), time division multiple access (TDMA), frequencydivision multiple access (FDMA), orthogonal frequency-division multipleaccess (OFDMA), single carrier frequency division multiple access(single Carrier FDMA, SC-FDMA), and carrier sense multiple access withcollision avoidance (CSMA/CA). Networks may be classified into a 2Gnetwork, a 3G network, a 4G network, or a future evolved network such asa 5G network based on factors such as capacities, rates, or delays ofdifferent networks. A typical 2G network includes a global system formobile communications (GSM) network or a general packet radio service(GPRS) network. A typical 3G network includes a universal mobiletelecommunications system (UMTS) network. A typical 4G network includesa long term evolution (LTE) network. The UMTS network sometimes may alsobe referred to as a universal terrestrial radio access network (UTRAN),and the LTE network sometimes may also be referred to as an evolveduniversal terrestrial radio access network (E-UTRAN). Based on differentresource allocation manners, the networks may be classified into acellular communications network and a wireless local area network(WLAN). The cellular communications network is dominated by scheduling,and the WLAN is dominated by contention. All the foregoing 2G, 3G, and4G networks are cellular communications networks. With development oftechnologies, the technical solutions provided in the embodiments of thepresent disclosure may be applied to a 4.5G or 5G network, or anothernon-cellular communications network. It may be understood that withdevelopment of technologies, the technical solutions provided in theembodiments of the present disclosure may also be applied to asubsequent evolved network, such as 6G. This is not limited herein. Forbrevity, a wireless communications network sometimes is referred to as anetwork for short in the embodiments of the present disclosure. Thecellular communications network is a type of wireless communicationsnetwork, and connects a terminal device to a network device through aradio channel in a cellular wireless networking manner, so that userscan communicate with each other in an activity.

An example in which the embodiments of the present disclosure areapplied to the 5G communications system is used for description below.It should be noted that the solutions in the embodiments of the presentdisclosure may be further applied to another wireless communicationsnetwork, and a corresponding name may also be replaced with a name of acorresponding function in the another wireless communications network.

The technical solutions provided in the embodiments of the presentdisclosure are applicable to the 5G communications system. FIG. 3 andFIG. 4 show schematic diagrams of two network architectures to which thetechnical solutions provided in the embodiments of the presentdisclosure are applicable to the 5G system. A network shown in FIG. 4includes a network device and a terminal device 10, and FIG. 3 onlyshows one network device 20 and two terminal devices 10 that communicatewith the network device 20. A difference between the network shown inFIG. 4 and a network shown in FIG. 3 lies in that, in the network shownin FIG. 4 , some functions of the network device are implemented on adistributed unit (DU) 21, and the other functions of the network deviceare implemented on a centralized unit (CU) 22. For example, the CUimplements functions of RRC (radio resource control) and PDCP (packetdata convergence protocol) layers, and the DU implements functions ofRLC (radio link control), MAC (media access control), and PHY (physical)layers. Information on the RRC layer eventually becomes information onthe PHY layer, or is converted from information on the PHY layer.Therefore, in this architecture, higher layer signaling, such as RRClayer signaling or PHCP layer signaling, may also be considered as beingsent by the DU or sent by the DU+the RU. A plurality of DUs 21 may beconnected to a same CU 22. It should be noted that, each of the networksshown in FIG. 3 and FIG. 4 may include at least one network device, andthere may be at least one terminal device that communicates with onenetwork device. This is not limited to quantities of network devicesshown in FIG. 3 and FIG. 4 and quantities of terminal devices shown inFIG. 3 and FIG. 4 . It may be understood that the network device may bea CU node, a DU node, or a device including a CU node and a DU node. Inaddition, the CU may be categorized as a network device in a RAN, or theCU may be categorized as a network device in a core network CN. This isnot limited herein. In one embodiment, the technical solutions providedin the embodiments of the present disclosure may be further applied to aterminal device-centered network.

Some nouns in the embodiments of the present disclosure are explainedand described below, to facilitate understanding by a person skilled inthe art.

-   -   (1) CSI is information for channel state measurement and/or        reporting. For example, the CSI may include at least one of a        CSI-reference signal resource indicator (CRI), a rank indicator        (RI), a precoding matrix indicator (PMI), or channel quality        indicator (CQI).

The terminal device and/or the network device can obtain CSI through CSImeasurement and/or reporting, to perform data scheduling, therebyimproving transmission performance.

-   -   (2) Quasi-Co-Location (QCL) Type

In an existing LTE communications system, two QCL types, namely, a typeA and a type B, are defined. The type A defines that antenna ports of aTP meet a QCL relationship. The antenna port may be an antenna port forsending a reference signal, and the reference signal is, for example, atleast one of a synchronization signal, a demodulation reference signal(DMRS), and a CSI-reference signal (CSI-RS). The type B defines a QCLconfiguration of antenna ports between a plurality of TPs. The QCLconfiguration of the antenna ports between the plurality of TPs may beindicated by using a physical downlink shared channel (PDSCH) resourcemapping and quasi-colocation indicator (PDSCH RE mapping andquasi-co-location indicator, PQI) in downlink control information (DCI),and the PQI is of 2 bits. The PQI may be used to indicate aquasi-co-location relationship of antenna ports for one or more of achannel state information-reference signal (CSI-RS) which satisfies QCL,a DMRS, a phase tracking reference signal (PTRS), which is also referredto as a phase noise reference signal), and a synchronized signal block(SS block). The PTRS may also be referred to as a phase compensationreference signal (PCRS), the SS block includes one or more of asynchronization signal and a broadcast channel, and the synchronizationsignal includes a primary synchronization signal (PSS) and/or asecondary synchronization signal (SSS). In the embodiments of thepresent disclosure, the type A may correspond to a case of a samenetwork device with a same antenna panel in the NR communicationssystem, and the type B may correspond to a case of a same network devicewith different antenna panels in the NR communications system, or theType-B may correspond to a case of different network devices in the NRcommunications system.

All DMRS antenna ports corresponding to the type A and the type B meet aQCL relationship. The type A and the type B may correspond to thesingle-point transmission mode. For example, the single-pointtransmission mode may be single-site transmission, DPS transmission, orDPB transmission. For example, antenna ports 7 to 14 corresponding tothe type A or the type B all meet a QCL relationship.

When different data streams are transmitted for the terminal device, todistinguish quasi-co-location information of antenna ports correspondingto reference signals of the different data streams, differentquasi-co-location information is configured for the antenna portscorresponding to the reference signals of the different data streams.Therefore, some antenna ports for a same reference signal are notquasi-co-located. When QCL indication information indicates a QCL typeof a DMRS antenna port is a type C, it indicates that the terminaldevice and the network device use the coordinated multipointtransmission/reception mode. For example, the coordinated multipointtransmission/reception mode may be NCJT. A QCL relationship of DMRSantenna ports corresponding to the type C is different from a QCLrelationship of DMRS antenna ports corresponding to the type A or thetype B. For example, not all DMRS antenna ports of the type C have a QCLrelationship. For example, corresponding to the type C, the antennaports 7, 8, 11, and 13 meet a QCL relationship, and the antenna ports 9,10, 12, and 14 meet a QCL relationship. However, any one of the antennaports 7, 8, 11, and 13 and any one of the antenna ports 9, 10, 12, and14 do not meet a QCL relationship.

It should be noted that, names of various QCL types may be correspondingnames of the foregoing names, or may be replaced with other names ofcorresponding functions. This is not limited in the embodiments of thepresent disclosure.

-   -   (3) Interaction: Interaction in the embodiments of the present        disclosure is a process in which two parties that perform the        interaction transfer information to each other, where the        information transferred herein may be the same or different. For        example, if the two parties that perform the interaction are a        base station 1 and a base station 2, the base station 1 may        request information from the base station 2, and the base        station 2 provides the base station 1 with the information        requested by the base station 1. Certainly, the base station 1        and the base station 2 may request information from each other,        and the information requested herein may be the same or may be        different.    -   (4) “A plurality of” means two or more than two. The term        “and/or” describes an association relationship for describing        associated objects and represents that three relationships may        exist. For example, A and/or B may represent the following three        cases: Only A exists, both A and B exist, and only B exists. The        character “/” usually indicates an “or” relationship between the        associated objects. “At least one” means one or more. “At least        one of A and B”, similar to “A and/or B”, describes an        association relationship between associated objects and        represents that three relationships may exist. For example, at        least one of A and B may represent the following three cases:        Only A exists, both A and B exist, and only B exists.    -   (5) Nouns “network” and “system” are usually interchangeably        used, but meanings of the nouns can be understood by a person        skilled in the art. Information, signal, message, and channel        may be interchangeably used sometimes. It should be noted that        meanings expressed by the terms are consistent when differences        of the terms are not emphasized. “Of”, “relevant”, and        “corresponding” may be interchangeably used sometimes. It should        be noted that meanings expressed by the terms are consistent        when differences of the terms are not emphasized.

The following describes the technical solutions provided in the presentdisclosure with reference to the accompanying drawings in thisspecification. It should be noted that, a presentation sequence of theembodiments in the present disclosure represents only a sequence of theembodiments, and does not represent priorities of the technicalsolutions provided in the embodiments.

An embodiment of the present disclosure provides a communicationsmethod. FIG. 5-1 shows a procedure of interaction between a terminaldevice and a network device in the communications method, and the methodincludes the following operations.

Operation 501: The network device sends configuration information to theterminal device.

In this embodiment, the network device determines a manner in which theterminal device is required to perform CSI measurement and feedback, tobe specific, the network device determines a transmission mode in whichthe terminal device is required to perform CSI measurement and feedback,and then the network device determines the configuration informationbased on the manner in which the terminal device is required to performCSI measurement and feedback. The network device sends the configurationinformation to the terminal device through operation 501, and theterminal device may learn, based on the configuration information, howto perform CSI measurement and feedback, where the configurationinformation is related to CSI measurement behavior and/or CSI feedbackrelated information.

In this embodiment, methods for performing CSI measurement and feedbackby the terminal device vary depending on transmission modes. When theterminal device performs CSI measurement and feedback in the differenttransmission modes, configuration information determined by the networkdevice is also different. The configuration information is used by theterminal device to learn how to perform CSI measurement and feedback.That the network device determines a transmission mode in which theterminal device is required to perform CSI measurement and feedbackincludes the following three cases: Case 1: The network devicedetermines that the terminal device needs to perform CSI measurement andfeedback in a hybrid mode of a single-point transmission mode+acoordinated multipoint transmission/reception mode. Case 2: The networkdevice determines that the terminal device needs to perform CSImeasurement and feedback in a single-point transmission mode. Case 3:The network device determines that the terminal device needs to performCSI measurement and feedback in a coordinated multipointtransmission/reception mode. The three cases respectively correspond todifferent configuration information, and are described in detail below.

Operation 502: The terminal device determines the CSI measurementbehavior and/or the CSI feedback related information, where the channelstate information CSI measurement behavior and/or the CSI feedbackrelated information are/is related to the configuration information.

The CSI measurement behavior instructs the terminal device how tomeasure CSI, and the CSI feedback related information is relatedinformation when the terminal device feeds back the CSI to the networkdevice. For example, the CSI feedback related information may include atleast one of the following information: content (for example, at leastone of a CRI, an RI, a PMI, or a CQI) of the CSI feedback, bitinformation (for example, the bit information includes a bit widthand/or a rule for determining a bit width) of the content of the CSIfeedback, a coding scheme (for example, independent encoding or jointencoding) used by the content of the CSI feedback, an interleaving mode(for example, independent interleaving or joint interleaving), and amapping mode (for example, a mapped time-frequency resource and/or amapping rule).

Operation 503: The terminal device performs CSI measurement based on theconfiguration information and the CSI measurement behavior and/or theCSI feedback related information, to obtain at least one piece of CSI,and sends all or some of the at least one piece of CSI to the networkdevice.

The terminal device determines the CSI measurement behavior and/or theCSI feedback related information based on operation 502. In oneembodiment, operation 503 may be implemented in the following threemanners:

-   -   Implementation 1: The terminal device determines the CSI        measurement behavior and the CSI feedback related information        based on the configuration information in operation 502. In this        case, in operation 503, the terminal device may perform CSI        measurement based on the configuration information and the        determined CSI measurement behavior, to obtain the at least one        piece of CSI, and then send all or some of the at least one        piece of CSI to the network device based on the CSI feedback        related information and the configuration information.    -   Implementation 2: The terminal device determines only the CSI        measurement behavior based on the configuration information in        operation 502. In this case, in operation 503, the terminal        device may perform CSI measurement based on the configuration        information and the determined CSI measurement behavior, to        obtain the at least one piece of CSI, and then sends all or some        of the at least one piece of CSI to the network device based on        a predefined CSI feedback method. The predefined CSI feedback        method may be defined in a protocol, or may be defined through        negotiation between the terminal device and the network device.        For example, the CSI feedback method that is predefined or        defined through negotiation may be a CSI feedback method in the        prior art. This is not limited in this embodiment. In one        embodiment, the terminal device may send all or some of the at        least one piece of CSI to the network device based on predefined        CSI feedback method and the configuration information.    -   Implementation 3: The terminal device determines only the CSI        feedback related information based on the configuration        information in operation 502. In this case, in operation 503,        the terminal device may perform CSI measurement based on a        predefined CSI measurement method, to obtain the at least one        piece of CSI, and then send all or some of the at least one        piece of CSI to the network device based on the configuration        information and the CSI feedback related information. The        predefined CSI measurement method may be defined in a protocol,        or may be predefined through negotiation between the terminal        device and the network device, and may alternatively be a CSI        measurement method in the prior art. This is not limited in this        embodiment. In one embodiment, the terminal device may perform        CSI measurement based on the predefined CSI measurement method        and the configuration information, to obtain the at least one        piece of CSI.

In one embodiment, the configuration information may be determined basedon Case 1. In Case 1, the network device determines that the terminaldevice needs to perform CSI measurement and feedback in the hybrid modeof the single-point transmission mode+the coordinated multipointtransmission/reception mode, and in operation 503, the terminal deviceperform CSI measurement, to obtain two or more pieces of CSI, and theterminal device sends some or all of the obtained pieces of CSI to thenetwork device. When feeding back some of the pieces of CSI, theterminal device may feed back, to the network device, at least one of ameasurement manner, a measurement resource, or a transmission modecorresponding to the some of the pieces of CSI that are currently fedback. In this way, which one of the single-point transmission mode andthe coordinated multipoint transmission/reception mode has betterperformance can be indicated to the network device.

In one embodiment, the configuration information may be determined basedon Case 2. In Case 2, the network device determines that the terminaldevice needs to perform CSI measurement and feedback in the single-pointtransmission mode, and in operation 503, the terminal device performsCSI measurement, to obtain one or more pieces of CSI, and the terminaldevice sends some or all of the obtained pieces of CSI to the networkdevice, to indicate performance of the single-point transmission mode tothe network device.

In one embodiment, the configuration information may be determined basedon Case 3. In Case 3, the network device determines that the terminaldevice needs to perform CSI measurement and feedback in the coordinatedmultipoint transmission/reception mode, and in operation 503, theterminal device performs CSI measurement, to obtain one or more piecesof CSI, and the terminal device sends all or some of the obtained piecesof CSI to the network device, to indicate performance of the coordinatedmultipoint transmission/reception mode to the network device.

In a process in which the network device receives the CSI from theterminal device through operation 503, because the CSI measurementbehavior and/or the CSI feedback related information are/is related tothe configuration information, and the configuration information is sentby the network device to the terminal device, the network device cancorrectly receive (for example, at least one of decode or de-interleave)the CSI from the terminal device based on the CSI measurement behaviorand/or the CSI feedback related information that are/is indicated by thenetwork device to the terminal device. The network device receives theCSI from the terminal device by using a method corresponding to a methodfor performing CSI measurement and feedback by the terminal device. Tobe specific, the network device receives the CSI from the terminaldevice based on the CSI measurement behavior and/or the CSI feedbackrelated information. It should be noted that, when the network devicelearns of the method for performing CSI measurement and feedback by theterminal device, a method for receiving the CSI by the network devicemay be the same as that in the prior art. Details are not describedherein again.

In the communications method shown in FIG. 5-1 , because the networkdevice determines, based on a manner in which the terminal device isrequired to perform CSI measurement and feedback, namely, a transmissionmode in which the terminal device is required to perform CSI measurementand feedback, to send the configuration information to the terminaldevice, and the terminal device may learn, based on the configurationinformation, how to perform CSI measurement and feedback. Therefore,according to the communications method shown in FIG. 5-1 , even if theterminal device cannot determine the transmission mode in which CSImeasurement and feedback need to be performed, the terminal device mayalso learn, based on the configuration information sent by the networkdevice, how to perform CSI measurement and/or feedback, so that in ascenario in which a plurality of transmission modes are supported, theterminal device measures CSI, and feeds back the measured CSI to thenetwork device. In the communications method shown in FIG. 5-1 , theterminal device determines the CSI measurement behavior and/or the CSIfeedback related information based on the existing configurationinformation, thereby reducing signaling overheads. When a resource isconfigured in the configuration information, the terminal device canperform CSI measurement and feedback in the plurality of transmissionmodes. Compared with configuration of CSI measurement and feedback inone transmission mode once, signaling overheads can be reduced,reference signal overheads can be reduced, a delay of CSI measurementand feedback can be reduced, and performance can be improved. If theterminal device feeds back only CSI in a transmission mode with optimaltransmission performance, feedback overheads can be reduced, and thenetwork device is assisted in performing data scheduling based on theoptimal transmission mode. Alternatively, if the terminal device canfeed back CSI in the plurality of transmission modes, the network devicemay obtain transmission performance statuses in the plurality oftransmission modes, to assist data scheduling and improve performance.

The configuration information and the corresponding CSI measurementbehavior and/or CSI feedback related information in various cases aredescribed in detail below based on the foregoing three cases.

An assumed scenario is that the terminal device supports CSI measurementand feedback in the hybrid mode, and supports CSI measurement andfeedback in the single-point transmission mode. In this scenario, basedon Case 1, to be specific, the network device determines that theterminal device needs to perform CSI measurement and feedback in thehybrid mode of the single-point transmission mode+the coordinatedmultipoint transmission/reception mode, the configuration informationsent by the network device to the terminal device meets at least one ofthe following conditions (1) to (12), and the terminal device may learn,based on the configuration information that meets at least one of thefollowing conditions (1) to (12), how to perform CSI measurement andfeedback, that is, learn to perform CSI measurement and feedback in thehybrid mode of the single-point transmission mode+the coordinatedmultipoint transmission/reception mode.

The hybrid mode of the single-point transmission mode+the coordinatedmultipoint transmission/reception mode is referred to as a hybrid mode(which may also be referred to as a hybrid transmission mode) for shortbelow.

-   -   (1) The configuration information includes N1 non-zero power        (NZP) CSI-RS resources of a class A, where N1 is a positive        integer greater than or equal to 2.

In one embodiment, in an LTE communications system, that theconfiguration information includes N1 NZP CSI-RS resources of a class Ameans that the configuration information includes configurationinformation of one CSI process. That the network device sends theconfiguration information means that the network device sendsconfiguration information of one CSI process. N1 NZP CSI-RS resources ofthe class A are configured in the CSI process. For example, N1 may be 2.If two NZP CSI-RS resources of the class A are not configured in a CSIprocess corresponding to single-point transmission mode, theconfiguration information including one CSI process in which two NZPCSI-RS resources of the class A are configured may be used to determinethat the network device requires the terminal device to perform CSImeasurement and feedback in the hybrid mode. If the two NZP CSI-RSresources configured in the CSI process are not limited to being of theclass A in the configuration information, the two NZP CSI-RS resourcesmay be of the class A or a class B or the class A+a class B. Therefore,other information in the configuration information further needs to beused to indicate that the network device requires the terminal device toperform CSI measurement and feedback in the hybrid mode.

In an NR communications system, that the configuration informationincludes N1 NZP CSI-RS resources of a class A may mean that theconfiguration information includes one CSI reporting setting, where thereporting setting is associated with R pieces of association information(link) used for channel measurement, to be specific, associated with Rreference signal settings (RS setting), each RS setting includes atleast one NZP CSI-RS resource of the class A, and the R RS settingsinclude the N1 NZP CSI-RS resources of the class A; or the configurationinformation includes one reporting setting, where the reporting settingis associated with one piece of association information, namely, a link,used for channel measurement, to be specific, associated with one RSsetting, and the RS setting includes the N1 NZP CSI-RS resources of theclass A. For example, N1 may be 2.

In this embodiment, an NZP CSI-RS resource of the class A is anon-beamformed CSI-RS resource, namely, a CSI-RS resource on which abeamforming or precoding operation is not performed before the CSI-RSresource is sent.

An NZP CSI-RS resource of the class B is a beamformed CSI-RS resource,namely, a CSI-RS resource on which a beamforming or precoding operationis performed before the CSI-RS resource is sent.

-   -   (2) The configuration information includes N2 NZP CSI-RS        resources of a class B and CSI measurement behavior indication        information and/or CSI feedback related information indication        information, where N2 is a positive integer greater than or        equal to 2.

When how to perform CSI measurement and feedback is determined based ona resource included in the configuration information, if theconfiguration information includes N2 NZP CSI-RS resources of the classB, it cannot be determined, based only on the condition, that thenetwork device requires the terminal device to perform CSI measurementand feedback in the hybrid mode. In this case, the CSI measurementbehavior indication information and/or the CSI feedback relatedinformation indication information further need/needs to be used todetermine that the network device requires the terminal device toperform CSI measurement and feedback in the coordinated multipointtransmission/reception mode. The N2 NZP CSI-RS resources of the class Bthat are included in the configuration information may be used for bothchannel measurement and interference measurement, and the terminaldevice may perform CSI measurement on the resources, to obtain CSI.

In one embodiment, if the configuration information includes N3 NZPCSI-RS resources of the class B, where N3 is a positive integer greaterthan or equal to 2, and it is predefined in a protocol that when thereare N3 NZP CSI-RS resources of the class B, the terminal device performsCSI measurement and feedback in the hybrid mode, the CSI measurementbehavior indication information and/or the CSI feedback relatedinformation indication information may not be used to determine that thenetwork device requires the terminal device to perform CSI measurementand feedback in the coordinated multipoint transmission/reception mode.That is, the CSI measurement behavior and/or the CSI feedback relatedinformation are/is determined based on the N3 NZP CSI-RS resources ofthe class B.

-   -   (3) The configuration information includes CSI measurement        behavior indication information and/or CSI feedback related        information indication information.

In the foregoing conditions (2) and (3), the CSI measurement behaviorindication information indicates the CSI measurement behavior, and theCSI measurement behavior is behavior of performing CSI measurement bythe terminal device in the hybrid mode; and the CSI feedback relatedinformation indication information indicates the CSI feedback relatedinformation, and the CSI feedback related information is relatedinformation used when the terminal device feeds back the CSI in thehybrid mode. Information related to the behavior of performing CSImeasurement by the terminal device in the hybrid mode and the relatedinformation used when the terminal device feeds back the CSI in thehybrid mode are described below.

The terminal device may directly determine the CSI measurement behaviorand/or the CSI feedback related information based on the configurationinformation that meets the condition (3), so that the terminal devicedoes not need to perform determining and selection, thereby reducingcomplexity of the terminal device.

-   -   (4) The configuration information includes a QCL type of an        antenna port that is a type C.

In the LTE communications system, when the configuration informationincludes the QCL type of the antenna port that is the type C, if theconfiguration information includes the CSI process quantity that is 1,it may be determined, based on the QCL type that is the type C, that thenetwork device requires the terminal device to perform CSI measurementand feedback in the hybrid mode. The reason is as follows: It may bedetermined, based on the QCL type that is the type C, that a current CSIprocess is a CSI process in the coordinated multipointtransmission/reception mode. A feature of the CSI process is that K NZPCSI-RS resources and one CSI-interference measurement (CSI-IM) resourceare configured. K is an integer not less than 2.

In the LTE communications system, when the configuration informationincludes the QCL type of the antenna port that is the type C, if theconfiguration information includes more than one CSI process, it cannotbe determined, based on the QCL type that is the type C, that thenetwork device requires the terminal device to perform CSI measurementand feedback in the hybrid mode, and other information in theconfiguration information may be further used for determining, forexample, the condition (1) may be used for determining. To be specific,if the configuration information includes the QCL type of the antennaport that is the type C, the configuration information includes the CSIprocess quantity that is 1, and N1 NZP CSI-RS resources of a class A areconfigured in the CSI process, it may be determined that the networkdevice requires the terminal device to perform CSI measurement andfeedback in the hybrid mode. When more than one CSI process is included,it is determined, based on both the QCL type of the antenna port that isthe type C and a quantity of NZP CSI-RS resources configured in theplurality of CSI processes, that a current CSI process is a CSI processin the coordinated multipoint transmission/reception mode.

In one embodiment, when the QCL type is the type C, the CSI measurementbehavior and/or the CSI feedback related information may alternativelybe determined with reference to another condition, for example, at leastone item in the configuration information in (1) to (12) or anothercondition. This is not specifically limited herein.

In the NR communications system, for a QCL type of an antenna port, onlyone QCL type, for example, a QCL type C, may be defined. Alternatively,similar to the LTE communications system, a plurality of QCL types, forexample, three QCL types, namely, a type A, a type B, and a type C, maybe defined. Other QCL types may be further defined, or QCL types may beclassified based on other features. This is not specifically limitedherein. In this way, when a plurality of QCL types are defined, the CSImeasurement behavior and/or the CSI feedback related information mayalternatively be determined in the NR communications system based on theQCL types.

The terminal device determines the CSI measurement behavior and/or theCSI feedback related information based on the configuration informationthat meets the condition (4), in other words, based on the existingconfiguration information, to implement CSI measurement and feedback.Compared with a case in which dedicated information is configured toindicate the CSI measurement behavior and/or the CSI feedback relatedinformation, the foregoing method can reduce signaling overheads.

-   -   (5) The configuration information includes a QCL type of an        antenna port that is a type C and a CSI process quantity that is        1.

The condition (5) is applicable to the LTE communications system. Whenthe configuration information meets the condition (5), it may bedetermined that the network device requires the terminal device toperform CSI measurement and feedback in the hybrid mode.

-   -   (6) The configuration information includes a PQI that indicates        that a QCL quantity is greater than M, where M is a positive        integer greater than or equal to 1.    -   (7) The configuration information includes a PQI that indicates        that a parameter group quantity is greater than P, where P is a        positive integer greater than or equal to 1.    -   (8) The configuration information includes at least one of bit        information for CRI reporting, bit information for CRI and RI        reporting, and bit information for RI reporting.

If at least one of bit information for CRI reporting, bit informationfor CRI and RI reporting, and bit information for RI reporting that areused when the network device requires the terminal device to perform CSImeasurement and feedback in the single-point transmission mode may be apredefined value, the configuration information does not need to includeat least one of the bit information for CRI reporting, the bitinformation for CRI and RI reporting, and the bit information for RIreporting, so that when the configuration information meets thecondition (8), it may be determined that the network device requires theterminal device to perform CSI measurement and feedback in the hybridmode, and the bit information included in the configuration informationis bit information used when the terminal device performs CSImeasurement and feedback in the hybrid mode. If one or more of the bitinformation for CRI reporting, the bit information for CRI and RIreporting, and the bit information for RI reporting that are used whenthe network device requires the terminal device to perform CSImeasurement and feedback in the single-point transmission mode are alsoconfigured by using the configuration information, when theconfiguration information meets the condition (8), it is furtherdetermined, with reference to other information in the configurationinformation, for example, with reference to the configurationinformation in at least one of other conditions than (8) in (1) to (12)or another condition, that the network device requires the terminaldevice to perform CSI measurement and feedback in the hybrid mode. Thisis not specifically limited herein, for example, a quantity of NZPCSI-RS resources is not limited.

-   -   (9) The configuration information includes that when bit        information for CRI reporting is L and there are K NZP CSI-RS        resources, L≠┌log₂ K┐.

In one embodiment, the NZP CSI-RS resource may be a resource for channelmeasurement, a resource for interference measurement, or a resource forboth channel measurement and interference measurement, or may include atotal resource including a resource for channel measurement and aresource for interference measurement. This is not specifically limitedherein.

When the configuration information meets the condition (9), it may bedetermined that the network device requires the terminal device toperform CSI measurement and feedback in the hybrid mode, and the bitinformation for CRI reporting that is included in the configurationinformation is bit information for CRI reporting that is used when theterminal device performs CSI measurement and feedback in the hybridmode.

The bit information for CRI reporting may be configured by using higherlayer signaling or physical layer signaling. The higher layer signalingmay be RRC signaling or MAC (media access control) layer signaling. Thisis not specifically limited herein.

For example, higher layer signaling CRI-bitsize=2 indicates that the bitinformation for CRI reporting is 2. For another example, bit informationof a plurality of CRIs is configured by using higher layer signaling,and bit information of one CRI is triggered (activated) in the bitinformation of the plurality of CRIs by using physical layer signaling,as the bit information for CRI reporting.

In one embodiment, for example, in the LTE communications system, whenthe bit information for CRI reporting is L, there are K NZP CSI-RSresources, and L≠┌log₂ K┐ is met, the terminal device determines whethera current CSI process is a CSI process in the coordinated multipointtransmission/reception mode, to be specific, whether CSI measurement andfeedback need to be performed in the hybrid mode. For example, if thebit information for CRI reporting is 2, and there are two NZP CSI-RSresources, because L≠┌log₂ K┐ is met, it may be determined that CSImeasurement and feedback need to be performed in the hybrid mode.

In one embodiment, for example, in the NR communications system, higherlayer signaling may be configured in a reporting setting. For example,higher layer signaling CRI-bit-size is included in ReportConfig. Whenthe bit information for CRI reporting is L, there are K NZP CSI-RSresources, and L≠┌log₂ K┐ is met, the terminal device determines thatCSI measurement and feedback need to be performed in the hybrid mode.

The CSI measurement behavior and/or CSI feedback related informationare/is determined based on the configuration information, in otherwords, based on the existing configuration information, to implement CSImeasurement and/or feedback. Compared with a case in which dedicatedinformation is configured to indicate the CSI measurement behaviorand/or the CSI feedback related information, signaling overheads can bereduced.

-   -   (10) The configuration information includes one reporting        setting, where the reporting setting is associated with at least        one of Q channel links, T RS settings, and S RS sets, where Q is        a positive integer greater than or equal to 2, T is a positive        integer greater than or equal to 2, and S is a positive integer        greater than or equal to 2. The network device configures three        sets for the terminal device, which are respectively a CSI        reporting setting, a reference signal setting (RS setting), and        a CSI measurement setting. The CSI measurement setting includes        association information (link), and each piece of association        information corresponds to one CSI reporting setting and one        resource setting.

The reporting setting is used to indicate reporting parameterinformation, for example, at least one of a CSI reporting parameter (forexample, at least one of an RI, a PMI, a CQI, or a CRI), a CSI type (forexample, a type I and/or a type II), codebook configuration information(for example, codebook limitation information), time domain behavior, afrequency domain granularity (for example, at least one of a PMI and/orCQI reporting granularity, a full bandwidth, a subband, or a partialsubband), or a measurement limitation configuration.

Each RS setting includes at least one reference signal set (RS set,which may also be referred to as an RS resource set (reference signalresource set)), and each reference signal set includes at least onereference signal resource. For example, for the CSI-RS, one RS settingmay include at least one CSI-RS resource set, and each CSI resource setmay include at least one CSI-RS resource. The configuration informationincludes at least one of mapped resource elements REs, a quantity ofantenna ports, time domain behavior, or the like.

Each piece of association information in the measurement settingincludes one or more of a CSI reporting setting identifier, a resourcesetting identifier, or a measurement attribute (for example, a channelor interference).

That the configuration information includes one reporting setting, wherethe reporting setting is associated with at least one of Q channellinks, T RS settings, and S RS sets, where Q is a positive integergreater than or equal to 2, T is a positive integer greater than orequal to 2, and S is a positive integer greater than or equal to 2 meansthat, the configuration information includes one reporting setting,where the reporting setting is associated with the Q channel linksand/or the T RS settings and/or the S RS sets. That the configurationinformation includes one reporting setting that is associated with atleast one of the Q channel links, the T RS settings, and the S RS setsshould not be understood as any one of the following three descriptions:The configuration information includes one reporting setting that isassociated with at least one of the Q channel links, the configurationinformation includes one reporting setting that is associated with atleast one of the T RS settings, and the configuration informationincludes one reporting setting that is associated with at least one ofthe S RS sets. For example, a value of Q may be 2.

-   -   (11) The configuration information includes a first resource and        a second resource, where the first resource is a resource used        to measure at least one of first CSI, second CSI, and third CSI,        and the second resource is a resource used to measure fourth        CSI.

The first CSI is obtained based on interference power; the second CSI isobtained based on interference that is obtained by using a presetalgorithm when a resource used for channel measurement is the same as aresource used for interference measurement; the third CSI is obtainedbased on interference power and interference that is obtained by using apreset algorithm when a resource used for channel measurement is thesame as a resource used for interference measurement; the presetalgorithm may be that interference is equal to a difference between areceived signal and a wanted signal; and the fourth CSI is obtainedbased on inter-stream interference or inter-codeword interference.Explanations of the first CSI, the second CSI, the third CSI, and thefourth CSI in this embodiment are applicable to other embodiments of thepresent disclosure.

In one embodiment, for example, interference to the first CSI may beobtained through measurement performed only by configuring aninterference measurement resource as a ZP CSI-RS resource. To bespecific, interference power is measured by using the ZP CSI-RSresource, and CSI is calculated based on the interference power.

In one embodiment, for example, interference to the second CSI may beobtained through measurement performed by configuring a resource forchannel measurement and a resource for interference measurement as asame CSI-RS resource. The terminal device processes a received signaland a wanted signal based on the CSI-RS resource, to obtain interferenceinformation, for example, subtract the wanted signal from the receivedsignal, to obtain the interference information.

In one embodiment, for example, for interference to the third CSI, afirst interference measurement resource may be configured as a ZP CSI-RSresource, a second interference measurement resource may also beconfigured, and the second interference measurement resource is aresource for both channel measurement and interference measurement.First interference information, namely, interference power, is obtainedby using the first interference measurement resource, secondinterference information is obtained based on the second interferencemeasurement resource, and total interference information is obtainedbased on the first interference information and the second interferenceinformation. For example, the interference power is added to the secondinterference information to obtain the total interference information.

In one embodiment, for example, interference to the fourth CSI may beobtained by configuring an NZP CSI-RS resource for interferencemeasurement. In one embodiment, when interference measurement isperformed by using the NZP CSI-RS resource, interference may be obtainedafter a channel that is measured by using the resource and a precodingmatrix corresponding to the resource are processed.

Measurement of at least one of the first CSI, the second CSI, and thethird CSI indicates that the terminal device needs to perform CSImeasurement and feedback in the single-point transmission mode, andmeasurement of the fourth CSI indicates that the terminal device needsto perform CSI measurement and feedback in the coordinated multipointtransmission/reception mode. Therefore, when the configurationinformation includes the first resource and the second resource, itindicates that the terminal device needs to perform CSI measurement andfeedback in the hybrid mode.

This embodiment provides a method for determining CSI measurement and/orfeedback corresponding to a resource. This part may be applied incombination with another part of this embodiment, or may beindependently applied. The method is specifically described as follows:

In one embodiment, in the NR communications system, if one reportingsetting is associated with more than Q links, the network device maynotify, by using the configuration information in a manner in thecondition (11), the terminal device of resources used for CSImeasurement in the single-point transmission mode and resources used forCSI measurement in the coordinated multipoint transmission/receptionmode in the associated links.

If one reporting setting is associated with more than Q links, resourcesused for CSI measurement in the single-point transmission mode andresources used for CSI measurement in the coordinated multipointtransmission/reception mode in the associated links may alternatively bepredefined. For example, it is determined, by using resource identifierinformation, that the resource is a resource that is used for performingCSI measurement and/or feedback in the hybrid mode. For example, twochannel measurement resources with smaller index numbers that areconnected to a resource set are predefined as resources used for CSImeasurement in the coordinated multipoint transmission/reception mode.Example 1: One reporting setting is associated with three channelmeasurement resources that are respectively an NZP CSI-RS 1, an NZPCSI-RS 2, and an NZP CSI-RS 3. In this case, the NZP CSI-RS 1 and theNZP CSI-RS 2 may be predefined as resources used for CSI measurement inthe coordinated multipoint transmission/reception mode, or the NZPCSI-RS 2 and the NZP CSI-RS 3 may be predefined as resources used forCSI measurement in the coordinated multipoint transmission/receptionmode. Example 2: One reporting setting is associated with three linksthat are respectively a link 1, a link 2, and a link 3. In this case,the link 1 and the link 2 may be predefined as resources used for CSImeasurement in the coordinated multipoint transmission/reception mode,or the link 1 and the link 2 may be predefined as resources used for CSImeasurement in the single-point transmission mode.

In one embodiment, indication information may be configured to indicateresources used for CSI measurement in the single-point transmission modeand resources used for CSI measurement in the coordinated multipointtransmission/reception mode. Example 1: An example in which indicationinformation is configured in resource configurations of an NZP CSI-RS 1and an NZP CSI-RS 2 is used. The indication information in the resourceconfiguration of the NZP CSI-RS 1 is “joint measurement=TRUE” (forexample, a corresponding information element or field has a specificvalue, such as 1), and the indication information in the resourceconfiguration of the NZP CSI-RS 2 is “joint measurement=TRUE” (forexample, a corresponding information element or field has a specificvalue, such as 1). When the indication information is “jointmeasurement=TRUE”, it indicates that the resource is a resource used forCSI measurement in the coordinated multipoint transmission/receptionmode. Example 2: An example in which indication information isconfigured in resource configurations of a link 1 and a link 2 is used.The indication information of the link 1 is “joint measurement=TRUE”(for example, a corresponding information element or field has aspecific value, such as 1), and the indication information of the link 2is “joint measurement=TRUE (for example, a corresponding informationelement or field has a specific value, such as 1)”. When the indicationinformation is “joint measurement=TRUE”, it indicates that the linkresource is a resource used for CSI measurement in the coordinatedmultipoint transmission/reception mode.

A schematic diagram of a resource configuration shown in FIG. 5-2 isused as an example: NZP 1 is a channel measurement resource, ZP 1 is aninterference measurement resource, and after performing CSI measurement,the terminal device calculates a CSI report 1, and the terminal devicefeeds back a CRI=1 and the CSI report 1. The CRI=1 indicates that achannel measurement resource for the CSI report 1 is a measurementresource with an index of 1. NZP 2 is a channel measurement resource,the ZP 1 is an interference measurement resource, and after performingCSI measurement, the terminal device calculates a CSI report 2, and theterminal device feeds back a CRI=2 and the CSI report 2. NZP 3 is achannel measurement resource, the ZP 1 is an interference measurementresource, and after performing CSI measurement, the terminal devicecalculates a CSI report 3, and the terminal device feeds back a CRI=3and the CSI report 3. Both the NZP 1 and the NZP 2 are channelmeasurement resources, and the ZP 1 is an interference measurementresource. The terminal device separately uses the NZP 1 and the NZP 2 tocalculate a channel. A channel part of a CQI of a CSI report a is ameasurement value on the NZP 1, and an interference part is a sum of ameasurement value on the NZP 2 and a measurement value on the ZP 1. Achannel part of a CQI of a CSI report b is a measurement value on theNZP 2, and an interference part is a sum of a measurement value on theNZP 1 and a measurement value on the ZP 1. The terminal device feedsback a CRI=4, the CSI report a, and the CSI report b. The CSI report 1and the CSI report 2 may be measurement results in a DPS mode, and theCSI report a and the CSI report b may be measurement results in an NCJTmode, where a and b are numbers of CSI information, and are used todistinguish from other CSI information, and specific values are notlimited herein.

Actually, the terminal device may obtain at least one of the CSI report1, the CSI report 2, the CSI report 3, the CSI report a, or the CSIreport b through measurement, and may selectively report CSI withoptimal transmission performance.

For example, if the NZP CSI-RS resource 1 has the optimal performance,the terminal device reports the CRI=1 and CSI corresponding to the CSIreport 1. If the NZP CSI-RS resource 2 has the optimal performance, theterminal device reports the CRI=2 and CSI corresponding to the CSIreport 2. If the NZP CSI-RS resource 3 has the optimal performance, theterminal device reports the CRI=3 and CSI corresponding to the CSIreport 3. If joint transmission of the NZP CSI-RS resource 1 and the NZPCSI-RS resource 2 has the optimal performance, the terminal devicereports the CRI=4 and CSI corresponding to the CSI report a and the CSIreport b.

-   -   (12) The configuration information includes indication        information, where the indication information instructs the        terminal device to perform CSI measurement and feedback in the        hybrid transmission mode. The indication information indicates        that a current CSI process is a CSI process in the coordinated        multipoint transmission/reception mode, and the terminal device        learns, based on the indication information, to perform CSI        measurement and feedback in the hybrid transmission mode.

In one embodiment, the indication information may be signaling. Forexample, in the LTE communications system, the indication informationmay be an NCJT CSI process indication, and when higher layer signalingCoMP-Process=TRUE (for example, a corresponding information element orfield has a specific value, such as 1), it indicates that a current CSIprocess is a CSI process in the coordinated multipointtransmission/reception mode, so that the terminal device is instructedto perform CSI measurement and feedback in the hybrid transmission mode.For another example, in the NR communications system, when higher layersignaling CoMP-Process=TRUE (for example, a corresponding informationelement or field has a specific value, such as 1), it indicates that theterminal device performs CSI measurement and feedback in the hybridtransmission mode. The higher layer signaling may be included in ameasurement configuration MeasConfig, or may be included in a reportingconfiguration ReportConfig.

In one embodiment, the indication information may indicate a firstresource and a second resource, the first resource is a resource used tomeasure at least one of first CSI, second CSI, and third CSI, and thesecond resource is a resource used to measure fourth CSI.

In one embodiment, indication information may be configured to indicateresources used for CSI measurement in the single-point transmission modeand resources used for CSI measurement in the coordinated multipointtransmission/reception mode. Example 1: An example in which indicationinformation is configured in resource configurations of an NZP CSI-RS 1and an NZP CSI-RS 2 is used. The indication information in the resourceconfiguration of the NZP CSI-RS 1 is “joint measurement=TRUE” (forexample, a corresponding information element or field has a specificvalue, such as 1), and the indication information in the resourceconfiguration of the NZP CSI-RS 2 is “joint measurement=TRUE” (forexample, a corresponding information element or field has a specificvalue, such as 1). When the indication information is “jointmeasurement=TRUE”, it indicates that the resource is a resource used forCSI measurement in the coordinated multipoint transmission/receptionmode. Example 2: An example in which indication information isconfigured in resource configurations of a link 1 and a link 2 is used.The indication information of the link 1 is “joint measurement=TRUE”(for example, a corresponding information element or field has aspecific value, such as 1), and the indication information of the link 2is “joint measurement=TRUE (for example, a corresponding informationelement or field has a specific value, such as 1)”. When the indicationinformation is “joint measurement=TRUE”, it indicates that the linkresource is a resource used for CSI measurement in the coordinatedmultipoint transmission/reception mode.

It should be noted that, when it is determined, based on the fact thatthe configuration information meets at least one of the foregoingconditions (1) to (12), that the network device requires the terminaldevice to perform CSI measurement and feedback in the hybrid mode, anapplicable scenario is that the terminal device supports CSI measurementand feedback in the hybrid mode, and supports CSI measurement andfeedback in the single-point transmission mode. If the scenario is thatthe terminal device supports CSI measurement and feedback in the hybridmode, supports CSI measurement and feedback in the single-pointtransmission mode, and supports CSI measurement and feedback in thecoordinated multipoint transmission/reception mode, when theconfiguration information meets at least one of the foregoing conditions(1) to (12), the network device may require the terminal device toperform CSI measurement and feedback in the hybrid mode, or the networkdevice may require the terminal device to perform CSI measurement andfeedback in the coordinated multipoint transmission/reception mode.Therefore, other information may be further used to indicate one of thetwo possibilities, for example, 1-bit information is used forindication, 0 indicates the former possibility, and 1 indicates thelatter possibility.

The terminal device may learn, based on the configuration informationthat meets at least one of the foregoing conditions (1) to (12), how toperform CSI measurement and feedback, which may also be understood aslearning to perform CSI measurement and feedback in the hybrid mode. Theterminal device may determine all or some CSI measurement behaviorand/or all or some CSI feedback related information based on theconfiguration information that meets at least one of the foregoingconditions (1) to (12), that is, the CSI measurement behavior and/or theCSI feedback related information are/is related to at least one of theforegoing conditions (1) to (12). It may be understood that, the CSImeasurement behavior and/or the CSI feedback related informationmentioned in the present disclosure do/does not represent all CSImeasurement behavior and/or all CSI feedback related information of theterminal device, and may be one or more of the CSI measurement behaviorand/or the CSI feedback related information, namely, all or some of theCSI measurement behavior and/or the CSI feedback related information.

In one embodiment, the determined CSI measurement behavior and/or CSIfeedback related information are/is described below. It may beunderstood that, the determined CSI measurement behavior and/or CSIfeedback related information are/is different from a design in the priorart. The CSI measurement behavior and/or the CSI feedback relatedinformation may be applied in combination with the foregoingconfiguration information, or may be separately applied, to provide aCSI measurement and/or feedback method. The determined CSI measurementbehavior and/or CSI feedback related information may be as follows:

-   -   1. The determined CSI measurement behavior includes measurement        of at least one of the first CSI, the second CSI, and the third        CSI, and measurement of the fourth CSI. The first CSI is        obtained based on the interference power; the second CSI is        obtained based on the interference that is obtained by using the        preset algorithm when the resource used for channel measurement        is the same as the resource used for interference measurement;        the third CSI is obtained based on the interference power and        the interference that is obtained by using the preset algorithm        when the resource used for channel measurement is the same as        the resource used for interference measurement; the preset        algorithm may be that interference is equal to the difference        between the received signal and the wanted signal; and the        fourth CSI is obtained based on the inter-stream interference or        the inter-codeword interference. Measurement of at least one of        the first CSI, the second CSI, and the third CSI is measurement        behavior when the terminal device performs CSI measurement in        the single-point transmission mode, and measurement of the        fourth CSI is measurement behavior when the terminal device        performs CSI measurement in the coordinated multipoint        transmission/reception mode.

In one embodiment, this part may be applied in combination with anotherpart of this embodiment, or may be independently applied, to provide aCSI measurement method.

If the configuration information includes the CSI measurement behaviorindication information, and the CSI measurement behavior indicationinformation indicates the CSI measurement behavior, the terminal devicemay determine the CSI measurement behavior based on the CSI measurementbehavior indication information. In an implementation, if the CSImeasurement behavior indication information instructs to measure atleast one of the first CSI, the second CSI, and the third CSI, andmeasure the fourth CSI, it is determined that the CSI measurementbehavior includes measurement of at least one of the first CSI, thesecond CSI, and the third CSI, and measurement of the fourth CSI.Further, the CSI measurement behavior indication information mayinstruct to measure which one or combination of more of the first CSI,the second CSI, and the third CSI and measure the fourth CSI. Forexample, the CSI measurement behavior indication information instructsto measure the first CSI and the fourth CSI; in this case, the CSImeasurement behavior includes measurement of the first CSI andmeasurement of the fourth CSI. For another example, the CSI measurementbehavior indication information instructs to measure the first CSI andthe second CSI and measure the fourth CSI; in this case, the CSImeasurement behavior includes measurement of the first CSI, the secondCSI, and the fourth CSI.

In one embodiment, if measurement of the fourth CSI is determined basedon the configuration information, the CSI measurement behaviorindication information may instruct to measure which one or combinationof more of the first CSI, the second CSI, and the third CSI. Forexample, the CSI measurement behavior indication information instructsto measure the first CSI; in this case, the CSI measurement behaviorincludes measurement of the first CSI and measurement of the fourth CSI.For another example, the CSI measurement behavior indication informationinstructs to measure the first CSI and the second CSI; in this case, theCSI measurement behavior includes measurement of the first CSI, thesecond CSI, and the fourth CSI. This is not specifically limited herein.

Alternatively, the terminal device may determine, based on theconfiguration information, that the network device requires the terminaldevice to perform CSI measurement and CSI feedback in the hybrid mode,and determine preconfigured CSI measurement behavior in the hybrid modeas CSI measurement behavior used by the terminal device. For example,the CSI measurement behavior includes measurement of at least one of thefirst CSI, the second CSI, and the third CSI, and measurement of thefourth CSI. Further, measurement of which one or combination of more ofthe first CSI, the second CSI, and the third CSI that is included in theCSI measurement behavior may be determined based on the configurationinformation. For example, a method is as follows:

The first CSI is obtained based on the interference power. Therefore, ifan interference measurement resource included in the configurationinformation includes a zero power CSI-RS resource, the CSI measurementbehavior includes measurement of the first CSI.

The second CSI is obtained based on the interference that is obtained byusing the preset algorithm when the resource used for channelmeasurement is the same as the resource for interference measurement.Therefore, if an interference measurement resource included in theconfiguration information includes a channel measurement resource and aninterference measurement resource that are the same, the CSI measurementbehavior includes measurement of the second CSI.

The third CSI is obtained based on the interference power and theinterference that is obtained by using the preset algorithm when theresource used for channel measurement is the same as the resource usedfor interference measurement. Therefore, if the configurationinformation includes the first interference measurement resource and thesecond interference measurement resource, the first interferencemeasurement resource is a zero power CSI-RS resource, and the secondinterference measurement resource is a resource that is the same as achannel measurement resource, it may be predefined that the CSImeasurement behavior includes measurement of only the third CSI, or itmay be predefined that the CSI measurement behavior includes measurementof the first CSI and the third CSI, or it may be predefined that the CSImeasurement behavior includes measurement of the second CSI and thethird CSI, or it may be predefined that the CSI measurement behaviorincludes measurement of the first CSI, the second CSI, and the thirdCSI.

In one embodiment, on the basis that the fourth CSI is obtained based onthe inter-stream interference or the inter-codeword interference, thefourth CSI may alternatively be obtained in a plurality of manners. Thisis not limited in this embodiment. For example, the fourth CSI may beobtained in the following four manners. First manner: The fourth CSI maybe obtained based only on the inter-stream interference or theinter-codeword interference.

Second manner: The fourth CSI may be obtained based on the inter-streaminterference or the inter-codeword interference, and may be furtherobtained based on interference power. That is, the fourth CSI isobtained based on the interference power and the inter-streaminterference or the inter-codeword interference.

Third manner: The fourth CSI may be obtained based on the inter-streaminterference or the inter-codeword interference, and may be furtherobtained based on interference that is obtained by using a presetalgorithm when a resource used for channel measurement is the same as aresource used for interference measurement. That is, the fourth CSI isobtained based on the interference that is obtained by using the presetalgorithm when the resource used for channel measurement is the same asthe resource used for interference measurement, and the inter-streaminterference or the inter-codeword interference. The preset algorithmmay be that the interference is equal to a difference between a receivedsignal and a wanted signal.

Fourth manner: The fourth CSI may be obtained based on the inter-streaminterference or the inter-codeword interference, and may be furtherobtained based on interference power and interference that is obtainedby using a preset algorithm when a resource used for channel measurementis the same as a resource used for interference measurement. That is,the fourth CSI is obtained based on the interference power, theinterference that is obtained by using the preset algorithm when theresource used for channel measurement is the same as the resource usedfor interference measurement, and the inter-stream interference or theinter-codeword interference.

Further, a specific manner of obtaining the fourth CSI in the foregoingmanners may be predefined, or the network device may notify the terminaldevice of a specific manner of obtaining the fourth CSI in the foregoingmanners. For example, the network device may notify, by using aninterference measurement resource related to the fourth CSI in theconfiguration information, the terminal device of the specific manner ofobtaining the fourth CSI in the foregoing manners. For example, if theinterference measurement resource related to the fourth CSI in theconfiguration information includes a zero power CSI-RS resource, thefourth CSI is further obtained based on the interference power. That is,the fourth CSI is obtained in the foregoing second manner.

It may be understood that, descriptions of one or more of the first CSIto the fourth CSI included in the CSI measurement behavior may beindependently applied, or may be applied in combination.

-   -   2. The determined CSI feedback related information includes use        of joint encoding or independent encoding for a CRI and an RI,        and/or a mapping mode of mapping a CRI and an RI to a        time-frequency resource. The use of joint encoding or        independent encoding for the CRI and the RI means that the CRI        and the RI are jointly encoded or separately encoded. Whether        joint encoding is performed on other information and the CRI        and/or the RI is not limited.

In one embodiment, this part may be applied in combination with anotherpart of this embodiment, or may be independently applied, to provide aCSI feedback method.

The terminal device may determine the CSI feedback related informationbased on the CSI feedback related information indication informationincluded in the configuration information. If the configurationinformation includes the CSI feedback related information indicationinformation, and the CSI feedback related information indicationinformation indicates the CSI feedback related information, the terminaldevice may determine the CSI feedback related information based on theCSI feedback related information indication information. In animplementation, if the CSI feedback related information indicationinformation indicates use of joint encoding for the CRI and the RI,and/or the CSI feedback related information indication informationindicates the mapping mode of mapping the CRI and the RI to thetime-frequency resource, it is determined that the CSI feedback relatedinformation includes use of joint encoding for the CRI and the RI,and/or the CSI feedback related information indication informationindicates the mapping mode of mapping the CRI and the RI to thetime-frequency resource. In another implementation, the CSI feedbackrelated information indication information indicates use of independentencoding for the CRI and the RI, and/or the CSI feedback relatedinformation indication information indicates the mapping mode of mappingthe CRI and the RI to the time-frequency resource, it is determined thatthe CSI feedback related information includes use of independentencoding for the CRI and the RI, and/or the CSI feedback relatedinformation indication information indicates the mapping mode of mappingthe CRI and the RI to the time-frequency resource.

Alternatively, the terminal device may determine, based on theconfiguration information, that the network device requires the terminaldevice to perform CSI measurement and CSI feedback in the hybrid mode,and determine preconfigured CSI feedback related parameter in the hybridmode as a CSI feedback related parameter used by the terminal device.The determined CSI feedback related information includes use of jointencoding or independent encoding for the CRI and the RI/or the mappingmode of mapping the CRI and the RI to the time-frequency resource. Inthe CSI feedback related information, a coding scheme used for the CRIand the RI is joint encoding or independent encoding. A specific codingscheme may be predefined, or may be notified by the network device tothe terminal device, for example, a specific coding scheme is notifiedby using other information in the configuration information.

In one embodiment, the CSI feedback related information may furtherinclude at least one of the bit information for CRI reporting, the bitinformation for CRI and RI reporting, and the bit information for RIreporting. When the CSI feedback related information includes use ofindependent encoding for the CRI and the RI, the CSI feedback relatedinformation may include the bit information for CRI reporting and thebit information for RI reporting. In this way, after performing CSImeasurement, the terminal device determines a CRI that meets the bitinformation for CRI reporting and an RI that meets the bit informationfor RI reporting, then independently encodes the CRI and the RI, andfinally maps the independently encoded CRI and RI to a time-frequencyresource in the mapping mode included in the CSI feedback relatedinformation. When the CSI feedback related information includes use ofjoint encoding for the CRI and the RI, the CSI feedback relatedinformation may include the bit information for CRI and RI reporting,and the CSI feedback related information may also include the bitinformation for CRI reporting and the bit information for RI reporting.The bit information for CRI and RI reporting may be determined based onthe bit information for CRI reporting and the bit information for RIreporting. In this way, after performing CSI measurement, the terminaldevice determines a CRI and an RI that meet the bit information for CRIand RI reporting, then jointly encodes the CRI and the RI, and finallymaps the jointly encoded CRI and RI to a time-frequency resource in themapping mode included in the CSI feedback related information.

A mapping mode used for mapping the CRI and the RI to the time-frequencyresource is not limited in this embodiment. Some possible mapping modesare described below by using examples.

In one embodiment, this part may be applied in combination with anotherpart of this embodiment, or may be independently applied, to provide aresource mapping method.

Example 1

In the LTE communications system, channel coding is performed on the CRIand channel coding is performed on the RI. To be specific, after the CRIand the RI are independently encoded, the CRI enters an interleaver toobtain an interleaved CRI, and the RI enters the interleaver to obtainan interleaved RI. That is, the CRI and the RI are separatelyinterleaved. Then, the CRI and the RI are mapped to the time-frequencyresource in any one of the following mapping modes. In this embodiment,it is not limited to first time domain mapping, first frequency domainmapping, or first layer mapping. The layer mapping is a concept in spacedomain, which is paratactic with a time domain and a frequency domain.

Mapping mode 1: The CRI is mapped to a symbol next to an acknowledgeinstruction (acknowledge, ACK)/negative acknowledge instruction(negative acknowledge, NACK) symbol next to an uplink pilot symbol.ACK/NACK is referred to as A/N for short below. First time domainmapping and then frequency domain mapping may be performed on the CRI.The RI is mapped to the symbol next to the A/N symbol next to the uplinkpilot symbol, but an RE occupied by the CRI is excluded. First timedomain mapping and then frequency domain mapping may be performed on theRI. Symbols 1 to 7 in FIG. 6 are used as an example. The symbols 1 to 7form a slot, an uplink pilot is mapped to the symbol 4, A/N is mapped tothe symbol 3 and the symbol 5, and a CRI and an RI are mapped to thesymbol 2 and the symbol 6. When the CRI and the RI are mapped to thesymbol 2 and the symbol 6, the CRI is first mapped to the symbol 2 andthe symbol 6 in time domain, and then the RI is mapped to resourceelements (RE) other than REs to which the CRI is mapped in the symbol 2and the symbol 6 in time domain. Alternatively, the CRI is first mappedto the symbol 2 and the symbol 6 in time domain, and then the CRI ismapped to resource elements (RE) other than REs to which the CRI ismapped in the symbol 2 and the symbol 6 in time domain. Specifically,whether CRI mapping is first performed or RI mapping is first performedmay be predefined based on a protocol, or may be based on specificimplementation of a system.

Mapping mode 2: The CRI is mapped to a symbol next to an A/N symbol nextto an uplink pilot symbol. The RI is mapped to a symbol next to a CRIsymbol next to the A/N symbol next to the uplink pilot symbol (that is,the CRI and the RI occupy different symbols on a same frequencyresource). Symbols 1 to 7 in FIG. 6 are used as an example. An uplinkpilot is mapped to the symbol 4, A/N is mapped to the symbol 3 and thesymbol 5, a CRI is mapped to the symbol 2 and the symbol 6, and an RI ismapped to the symbol 1 and the symbol 7.

Mapping mode 3: The CRI is mapped to a symbol on a side next to an A/Nsymbol next to an uplink pilot symbol. The RI is mapped to a symbol onthe other side next to the A/N symbol next to the uplink pilot symbol.It may be predefined that the CRI is mapped to the side next to the A/Nsymbol next to the uplink pilot symbol, and the RI is mapped to theother side next to the A/N symbol next to the uplink pilot symbol. Forexample, the CRI is mapped to a symbol with a smaller number on oneside, and the RI is mapped to a symbol with a larger number on the otherside.

For example, symbols 1 to 7 in FIG. 6 are used as an example. An uplinkpilot is mapped to the symbol 4, A/N is mapped to the symbol 3 and thesymbol 5, and a CRI is mapped to the symbol 2, and an RI is mapped tothe symbol 6. Symbols 8 to 14 in FIG. 6 are used as an example. Anuplink pilot is mapped to the symbol 11, A/N is mapped to the symbol 10and the symbol 12, a CRI is mapped to the symbol 9, and an RI is mappedto the symbol 13. For another example, in FIG. 6 , an uplink pilot ismapped to a symbol 4 and a symbol 11, and A/N is mapped to symbols 3, 5,10, and 12. CRI and RI mapping may be as follows: A CRI is mapped to asymbol 2 and a symbol 13, and an RI is mapped to a symbol 6 and a symbol9. The CRI and RI mapping may alternatively be as follows: An RI ismapped to a symbol 2 and a symbol 13, and a CRI is mapped to a symbol 6and a symbol 9.

Example 2

In the NR communications system, channel coding is performed on the CRIand channel coding is performed on the RI. To be specific, after the CRIand the RI are independently encoded, the CRI enters an interleaver toobtain an interleaved CRI, and the RI enters the interleaver to obtainan interleaved RI. That is, the CRI and the RI are separatelyinterleaved. The CRI is mapped to a PUCCH, for example, a long PUCCH;and the RI is mapped to an RE other than an RE occupied by the CRI inthe PUCCH to which the CRI is mapped. Alternatively, the RI is mapped toanother PUCCH, such as a short PUCCH, that is in a same scheduling unitin which the CRI is mapped but does not include a PUCCH to which the CRIis mapped. This embodiment is not limited to first time domain mapping,first frequency domain mapping, or first layer mapping; time domainmapping is not limited to front-to-back mapping or back-to-frontmapping; frequency domain mapping is not limited to ascending mapping ordescending mapping; layer mapping is not limited to ascending mapping ordescending mapping; and a code block group (CBG) is not limited toascending mapping or descending mapping.

Specifically, at least one of the following mapping methods may beincluded. Specific items to be used may be predefined in a protocol, ormay be notified by the network device to the terminal device. To bespecific, indication information is sent to indicate a specific mappingmethod. This is not specifically limited herein.

In one embodiment, this part may be applied in combination with anotherpart of this embodiment, or may be independently applied, to provide aresource mapping method.

Mapping method 1: The CRI is mapped to a symbol next to an A/N symbolnext to an uplink pilot symbol. The RI is mapped to an RE, other than anRE occupied by the CRI, in the symbol next to the A/N symbol next to theuplink pilot symbol. Symbols 1 to 7 in FIG. 6 are used as an example. Anuplink pilot is mapped to the symbol 4, A/N is mapped to the symbol 3and the symbol 5, and a CRI and an RI are mapped to the symbol 2 and thesymbol 6. When the CRI and the RI are mapped to the symbol 2 and thesymbol 6, the CRI is first mapped to the symbol 2 and the symbol 6 intime domain, and then the RI is mapped to REs other than REs to whichthe CRI is mapped in the symbol 2 and the symbol 6 in time domain.Alternatively, when the CRI and the RI are mapped to the symbol 2 andthe symbol 6, the RI may be first mapped to the symbol 2 and the symbol6 in time domain, and then the CRI may be mapped to resource elements(RE) other than REs to which the CRI is mapped in the symbol 2 and thesymbol 6 in time domain.

For this solution, the CRI and the RI may be sequentially mapped to asame symbol and mapped to different REs.

Symbols 1 to 7 in FIG. 7 are used as an example. A DMRS is mapped to thesymbols 1, 2, 5, and 6, and a CRI and an RI are mapped to the symbol 3and the symbol 7. The DMRS may be a basic (front-loaded) DMRS, or anadditional DMRS. The CRI is mapped to a symbol next to the front-loadedDMRS and/or a symbol next to the additional DMRS, or the CRI is mappedto a symbol next to the front-loaded DMRS. That is, the CRI and the RIare mapped to the symbol 3.

Mapping method 2: The CRI is mapped to a symbol next to an A/N symbolnext to an uplink pilot symbol. The RI is mapped to a symbol next to aCRI symbol next to the A/N symbol next to the uplink pilot symbol.Symbols 1 to 7 in FIG. 6 are used as an example. An uplink pilot ismapped to the symbol 4, A/N is mapped to the symbol 3 and the symbol 5,a CRI is mapped to the symbol 2 and the symbol 6, and an RI is mapped tothe symbol 1 and the symbol 7.

For this solution, the CRI and the RI may be sequentially mapped todifferent symbols and mapped to different symbols.

Mapping method 3: The CRI is mapped to a symbol on a side next to an A/Nsymbol next to an uplink pilot symbol. The RI is mapped to a symbol onthe other side next to the A/N symbol next to the uplink pilot symbol.It may be predefined that the CRI is mapped to the side next to the A/Nsymbol next to the uplink pilot symbol, and the RI is mapped to theother side next to the A/N symbol next to the uplink pilot symbol. Forexample, the CRI is mapped to a symbol with a smaller number on oneside, and the RI is mapped to a symbol with a larger number on the otherside.

Symbols 1 to 7 in FIG. 6 are used as an example. An uplink pilot ismapped to the symbol 4, and A/N is mapped to the symbol 3 and the symbol5. CRI and RI mapping may be as follows: A CRI is mapped to the symbol2, and an RI is mapped to the symbol 6. The CRI and RI mapping mayalternatively be as follows: An RI is mapped to the symbol 2, and a CRIis mapped to the symbol 6.

For this solution, the CRI and the RI may be sequentially mapped todifferent symbols and mapped to different symbols.

Mapping method 4: The CRI and the RI are mapped to REs that arerelatively close to an uplink pilot.

The CRI is mapped to a same symbol in which some REs occupied by theuplink pilot are located, and the RI is mapped to a same symbol in whichthe other REs occupied by the uplink pilot are located. The symbol towhich the CRI and the RI are mapped may be predefined. For example, itis predefined that the CRI is mapped to the first half of the symbolsoccupied by the uplink pilot, and the RI is mapped to the second half ofthe symbols occupied by the uplink pilot. FIG. 8 and FIG. 9 are used asan example. A DMRS is mapped to symbols 1, 2, 5, and 6, so that a CRI ismapped to the symbol 1 and the symbol 2, and an RI is mapped to thesymbol 5 and the symbol 6. REs to which the CRI and the RI are mappedmay be mapped in ascending or descending order of sequence numbers offrequency domain units from a frequency domain position to which anuplink RS is mapped.

For this solution, the CRI and the RI may be sequentially mapped to asame symbol and mapped to different REs.

In this embodiment, when the terminal device determines to perform CSImeasurement and feedback in the hybrid mode, when the CRI and the RI areencoded, interleaved, and mapped, CQI/PMI encoding, interleaving, andmapping solutions corresponding to a plurality of CSI reports may be thefollowing method 1 or method 2.

In one embodiment, this part may be applied in combination with anotherpart of this embodiment, or may be independently applied, to provide atleast one of an encoding method, an interleaving method, or a mappingmethod.

Method 1: A sequence of encoding, interleaving, and mapping CQI/PMIscorresponding to RIs is consistent with a sequence of the RIs in an RIcombination. For example, if the RI combination is {4, 3}, bits O₀O₁ . .. O_(m−1) of a CQI/PMI corresponding to the RI=4 and bits O_(m)O_(m+1) .. . O_(n−1) of a CQI/PMI corresponding to the RI=3 form an O₀O₁ . . .O_(n−1) input encoder. To be specific, a sequence of encoding theCQI/PMIs corresponding to the RIs is the same as a sequence for the RIsin the RI combination. The CQI/PMI corresponding to the RI=4 is firstinput into the encoder, and then the CQI/PMI corresponding to the RI=3is input into the encoder. A sequence of interleaving and mapping theCQI/PMIs corresponding to the RIs is consistent with a sequence of theRIs in the RI combination.

Method 2: A sequence of encoding, interleaving, and mapping CQI/PMIscorresponding to RIs is consistent with a sequence of NZP CSI-RSresource IDs used in channel measurement. For example, a CQI 1/PMI 1obtained by using the NZP CSI-RS 1 as a channel measurement resource anda CQI 2/PMI 2 obtained by using the NZP CSI-RS 2 as a channelmeasurement resource are sequentially input into an encoder and aninterleaver as a combination and are mapped. To be specific, a CQI/PMIO₀O₁ . . . O_(m−1) obtained through measurement by using a resource witha smaller NZP CSI-RS ID and a CQI/PMI O_(m)O_(m+1) . . . O_(n−1)obtained through measurement by using a resource with a larger NZPCSI-RS ID form an O₀O₁ . . . O_(n−1) input encoder, and are interleavedand mapped.

The CSI may include at least one of a PMI, an RI, or a CQI, so thatreporting of the CSI is related to reporting of at least one of the PMI,the RI, or the CQI. In this case, there is a reporting sequence of atleast one of the PMI, the RI, or the CQI during reporting. The followingdescribes an embodiment of a reporting sequence of the PMI and the CQIand a method for determining a bit width of content included in the CSI,for example, the PMI or the CQI. Methods for determining the reportingsequence and the bit width of the content included in the CSI in thisembodiment may be independently implemented, or may be applied incombination, or may be separately combined with other embodiments in thepresent disclosure. This is not specifically limited herein.

In one embodiment, in this embodiment of the present disclosure, a firstset may be CSI corresponding to the first NZP CSI-RS resource, and asecond set may be CSI corresponding to the second NZP CSI-RS resource.

In one embodiment, in this embodiment of the present disclosure, a firstset may be CSI corresponding to the first codeword (for example, acodeword 0), and a second set may be CSI corresponding to the secondcodeword (for example, a codeword 1).

In one embodiment, in this embodiment of the present disclosure, thefirst set, the first set, the first CSI set, the first set, and thefirst CSI set may have a same meaning, and may be replaced with eachother. In addition, the first set may be replaced with the CSI for thefirst codeword (for example, the codeword 0), the CSI corresponding tothe first NZP CSI-RS resource, or the like. This is not specificallylimited herein.

In one embodiment, in this embodiment of the present disclosure, thesecond set, the second set, the second CSI set, the second set, and thesecond CSI set may have a same meaning, and may be replaced with eachother. In addition, the second set may be replaced with the CSI for thesecond codeword (for example, the codeword 1), the CSI corresponding tothe second NZP CSI-RS resource, or the like. This is not specificallylimited herein.

There may be different reporting sequences (in this embodiment of thepresent disclosure, the reporting sequence may also be referred to as afeedback sequence) of PMIs and CQIs in a first set and a second set inone CSI process (or CSI reporting). For example, the terminal devicedetermines, based on the first indication information, to feed back atleast two CSI sets, where the at least two CSI sets include a first setof CSI and a second set of CSI, the first set of CSI includes a CQI ofthe first set and/or a PMI of the first set, and the second set of CSIincludes a CQI of the second set and/or a PMI of the second set.Reporting method 1: A CQI (including the CQI of the first set and/or theCQI of the second set) is first reported, and then a PMI (including thePMI of the first set and/or the PMI of the second set) is reported. Themethod 1 further includes at least one of the following several methods:

Method 1.1: If the first set includes only the CQI, and the second setalso includes only the CQI, the CQI of the first set and the CQI of thesecond set are sequentially reported.

Method 1.2: If the first set includes the CQI and the PMI, and thesecond set includes only the CQI, the CQI of the first set, the CQI ofthe second set, and the PMI of the first set are sequentially reported.

Method 1.3: If the first set includes the CQI and the PMI, and thesecond set includes the CQI and the PMI, the CQI of the first set, theCQI of the second set, the PMI of the first set, and the PMI of thesecond set are sequentially reported.

Method 1.4: If PMIs of each set include a first PMI and a second PMI,the first PMI (including the first PMI of the first set and/or the firstPMI of the second set) is first reported, and then the second PMI(including the second PMI of the first set and/or the second PMI of thesecond set) is reported.

Method 1.5: If PMIs of each set include a first PMI and a second PMI,the first PMI and/or the second PMI of the first set are/is firstreported, and then the first PMI and/or the second PMI of the second setare/is reported.

For example, in a wideband CQI reporting mode, if no PMI is fed back, acorresponding mode is a mode 1-0.

A specific mode to be used may be predefined in a protocol, or may bedetermined through interaction between a base station and the terminal,for example, notified by the base station to the terminal by usingsignaling.

For the reporting sequence of the PMI and the CQI, refer to thereporting method 1 described above. To be specific, the CQI (includingthe CQI of the first set and the CQI of the second set) is firstreported, and then the PMI (including the PMI of the first set and thePMI of the second set) is reported. A reporting method 2 is describedbelow.

Reporting method 2: The first set (including the CQI and/or the PMI ofthe first set) is first reported, and then the second set (including theCQI and/or the PMI of the second set) is reported. The method 2 furtherincludes at least one of the following several specific methods:

Method 2.1: If the first set includes the CQI and the PMI, and thesecond set includes only the CQI, the CQI of the first set, the PMI ofthe first set, and the CQI of the second set are sequentially reported.

Method 2.2: If the first set includes the CQI, and the second setincludes the CQI and the PMI, the CQI of the first set, the CQI of thesecond set, and the PMI of the second set are sequentially reported.

Method 2.3: If the first set includes the CQI and the PMI, and thesecond set includes the CQI and the PMI, the CQI of the first set, thePMI of the first set, the CQI of the second set, and the PMI of thesecond set are sequentially reported.

In one embodiment, in this embodiment, at least one of the bitinformation for CRI reporting, the bit information for CRI and RIreporting, and the bit information for RI reporting included in the CSIfeedback related information may be determined in any one of thefollowing manners.

In one embodiment, this part may be applied in combination with anotherpart of this embodiment, or may be independently applied, to provide aCSI feedback method or a CSI feedback related information determiningmethod.

-   -   Manner 1: At least one of the bit information for CRI reporting,        the bit information for CRI and RI reporting, and the bit        information for RI reporting is a predefined value, and both the        network device and the terminal device already know the        predefined value.

For example, the bit information for CRI reporting includes 2 bits, thebit information for RI reporting includes 4 bits, and the bitinformation for CRI and RI reporting includes 6 bits.

In the LTE communications system, in the single-point transmission mode,because a maximum layer quantity supported by the terminal device is 8,a maximum bit width for RI reporting for one piece of CSI is 3. In thecoordinated multipoint transmission/reception mode, it is assumed that abase station 1 and a base station 2 perform coordinated transmission, anRI 1 corresponds to the base station 1, an RI 2 corresponds to the basestation 2, and the RI 1 and the RI 2 are combined for reporting.Possible combination cases are as follows: {RI 1, RI 2}={1, 1}, {1, 2},{2, 1}, {2, 2}, {2, 3}, {3, 2}{3, 3}, {3, 4}, {4, 3}, and {4, 4}.Therefore, a maximum bit width for RI reporting is 4. In conclusion, thebit information for RI reporting may be 4 bits.

Possible values of the CRI are 0, 1, and 2, and meanings are as follows:the CRI=0 indicates that the base station 1 corresponding to the firstNZP CSI-RS resource is the optimal transmission performance; the CRI=1indicates that the base station 2 corresponding to the second NZP CSI-RSresource has the optimal transmission performance; and the CRI=2indicates that coordinated transmission of the base station 1 and thebase station 2 corresponding to two NZP CSI-RS resources has the optimalperformance. In conclusion, the bit information for CRI reporting may be2 bits.

For example, in Manner 1, the bit width of the CRI and/or the bit widthof the RI are/is determined based on second indication information.

In an example, in Manner 1, the bit width of the CRI and/or the bitwidth of the RI may be determined based on the second indicationinformation. The configuration information includes the secondindication information, where the second indication informationinstructs the terminal device to perform CSI measurement and feedback inthe hybrid transmission mode, or indicates that a current CSI process isa CSI process in the coordinated multipoint transmission/reception mode.

The bit width of the RI may be determined based on the second indicationinformation.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width usedwhen a single RI is reported and/or determining a total quantity of bitsoccupied by a plurality of RIs (or an RI combination) when the pluralityof RIs (or the RI combination) are reported. This is not specificallylimited herein.

Specifically, for example, when the second indication informationinstructs to enable FeCoMP-based CSI feedback, the bit width of the RIis fixed (for example, specified in a protocol), a CRI=0, a CRI=1, aCRI=2, and the like are not distinguished, and a quantity of antennaports and/or a capability of the terminal device are/is notdistinguished either.

The capability of the terminal device may be at least one of a maximumlayer quantity supported by the terminal (short for the terminaldevice), a maximum antenna port quantity supported by the terminal, amaximum transmission rate supported by the terminal, a transmission mode(for example, an open-loop mode, a closed-loop mode, a single-cell mode,or a coordinated mode) supported by the terminal, or the like.

For example, for an example in which two NZP CSI-RS resources areconfigured, when the second indication information instructs to enableFeCoMP-based CSI feedback, the bit width of the RI may be fixed to 4.Certainly, another value is also feasible. This is not limited herein.

In this embodiment of the present disclosure, when a base station (thenetwork device is described by using the base station as an example)determines to enable FeCoMP-based CSI feedback, the base station sendsthe second indication information, and determines that the bit width ofthe RI of the terminal is 4, to be specific, the bit width of the RI isrelated to the second indication information. When receiving the secondindication information, the terminal may determine the bit width of theRI based on the second indication information. For example, the bitwidth of the RI is 4.

When determining not to enable FeCoMP-based CSI feedback, the basestation does not send the second indication information, and determinesthe bit width of the RI based on the prior art. When not receiving thesecond indication information, the terminal may determine the bit widthof the RI based on the prior art. The determining the bit width of theRI in the prior art is that, for example, the bit width of the RI isrelated to the quantity of antenna ports and the capability of theterminal device. Specifically, for example, if the quantity of antennaports is 4, and the capability of the terminal device may supporttransmission of a maximum of four layers, the bit width of the RI is 2.

For descriptions of implementations of the terminal and the basestation, refer to other parts in this embodiment. An implementation ofthe terminal is as an example for description below.

An example in which two NZP CSI-RS resources are configured is usedbelow to describe determining the bit width of the CRI and/or the bitwidth of the RI based on a quantity of NZP CSI-RS resources and thesecond indication information.

Specifically, when two NZP CSI-RS resources are configured, and thesecond indication information indicates that CSI measurement andfeedback are FeCoMP-based CSI feedback, it may be determined that thebit width of the RI is 4, and the bit width of the CRI is 2.

The value herein is merely an example, and another value is alsofeasible. This is not specifically limited.

Specifically, the terminal may determine, by using the method in theforegoing embodiment, that the CSI measurement behavior is FeCoMP-basedCSI measurement. For example, the second indication information isconfigured, and the second indication information is used to enableFeCoMP-based CSI feedback, or enable coordinated multipointtransmission/reception-based CSI feedback, or enable hybrid transmissionmode-based CSI feedback. For example, the second indication informationis a higher layer parameter FeCoMPCSIEnabled, and determining isperformed by configuring the higher layer parameter FeCoMPCSIEnabled orconfiguring FeCoMPCSIEnabled=TRUE (to be specific, determining isperformed based on the second indication information). The followingembodiment is specifically described by using a solution in which thehigher layer parameter FeCoMPCSIEnabled is configured. A solution inwhich FeCoMPCSIEnabled=TRUE is configured is similar to this, anddetails are not described herein.

Bit mapping of the RI is described below, which may also be understoodas that the bit meaning of the RI is described.

This embodiment provides a method for determining the bit meaning of theRI. The method may be combined with the method for determining the bitwidth of the RI in Manner 1. A manner of determining bit mapping of theRI, namely, the bit meaning of the RI may include one of the followingimplementations.

-   -   Implementation 1 (or referred to as Method 1.1): The bit meaning        of the RI is determined based on the second indication        information.

In this embodiment of the present disclosure, when receiving the secondindication information, the terminal may determine the bit meaning ofthe RI based on the second indication information.

-   -   Implementation 2 (or referred to as Method 1.2): The bit meaning        of the RI is determined based on the second indication        information and a value of the CRI.

When the second indication information is set to FeCoMPCSIEnabled or avalue of FeCoMPCSIEnabled is TRUE, the bit width of the RI may bedetermined, for example, is 4.

In view of this, Implementation 2 (namely, Method 1.2) may also beunderstood as follows: The bit meaning of the RI is determined based onthe bit width of the RI and the value of the CRI. In other words, thedetermining the bit meaning of the RI based on the second indicationinformation and a value of the CRI includes: determining the bit widthof the RI based on the second indication information, and furtherdetermining the bit meaning of the RI based on the bit width of the RIand the value of the CRI.

This embodiment provides another method for determining the bit meaningof the RI. The determining method may be combined with another methodfor determining the bit width of the RI in this embodiment, for example,combined with the method for determining the bit width of the RI inMethod 2.2 or Method 3, or may be combined with another method fordetermining the bit width of the RI. Details are not described herein.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width of anRI used when a single RI is reported and/or determining a total quantityof bits occupied by a plurality of RIs (or an RI combination) when theplurality of RIs (or the RI combination) are reported. This is notspecifically limited herein.

This embodiment may be independently implemented, or may be applied incombination with another embodiment. This is not specifically limitedherein.

A. A Case in which the Bit Width of the RI is 2:

The bit meaning of the CRI and/or the bit meaning of the RI are/isdetermined based on the second indication information and at least oneof a quantity of NZP CSI-RS resources, a quantity of antenna ports foran NZP CSI-RS, capability information of the terminal device, the bitwidth of the RI, or the value of the CRI. In an example, the bit meaningof the RI may be determined based on the value of the CRI, the secondindication information, and at least one of the quantity of antennaports for an NZP CSI-RS, the capability information of the terminaldevice, or the bit width of the RI.

In one embodiment, the terminal determines the bit meaning of the RIbased on the quantity of antenna ports for an NZP CSI-RS resource, thevalue of the CRI, and the second indication information. For example,the terminal may determine the bit width of the RI based on the quantityof antenna ports for an NZP CSI-RS resource, and then determine the bitmeaning of the RI based on the bit width of the RI, the value of theCRI, and the second indication information.

In one embodiment, the terminal determines the bit meaning of the RIbased on the quantity of antenna ports for an NZP CSI-RS resource, thecapability information of the terminal device, the value of the CRI, andthe second indication information. For example, the terminal maydetermine the bit width of the RI based on the quantity of antenna portsfor an NZP CSI-RS resource and the capability information of theterminal device, and then determine the bit meaning of the RI based onthe bit width of the RI, the value of the CRI, and the second indicationinformation.

In one embodiment, the terminal determines the bit meaning of the RIbased on the bit width of the RI, the value of the CRI, and the secondindication information.

B. A Case in which the Bit Width of the RI is 3:

At least one of the bit meaning of the CRI or the bit meaning of the RIis determined based on the second indication information and at leastone of a quantity of NZP CSI-RS resources, a quantity of antenna portsfor an NZP CSI-RS, capability information of the terminal device, thebit width of the RI, or the value of the CRI. In an example, the bitmeaning of the RI may be determined based on the second indicationinformation and the bit width of the RI.

C. A Case in which the Bit Width of the RI is 4:

Possible Manner 1:

At least one of the bit meaning of the CRI or the bit meaning of the RIis determined based on the second indication information and at leastone of a quantity of NZP CSI-RS resources, a quantity of antenna portsfor an NZP CSI-RS, capability information of the terminal device, thebit width of the RI, or the value of the CRI. In an example, the bitmeaning of the RI may be determined based on the value of the CRI, thesecond indication information, and at least one of the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the bit width of the RI.

Possible Manner 2:

The bit meaning of the RI is determined based on the second indicationinformation and at least one of a quantity of NZP CSI-RS resources, aquantity of antenna ports for an NZP CSI-RS, capability information ofthe terminal device, the bit width of the RI, or the value of the CRI.In an example, the bit meaning of the RI may be determined based on thesecond indication information and the bit width of the RI.

In one embodiment, the terminal may determine the bit meaning of the RIbased on the second indication information and the bit width of the RI.

In one embodiment, the terminal may determine the bit meaning of the RIbased on the bit width of the RI.

Possible Manner 2: When the RI and the CRI are jointly fed back orjointly encoded, the bit width of the RI is enabled to be independent ofthe value of the CRI, to be specific, it can be ensured that the bitwidth of the CRI and the bit width of the RI are known by both thenetwork device and the terminal device, so that the network device cancorrectly receive or decode the CRI and the RI. In addition, because thebit width of the RI is related to the quantity of antenna ports and/orthe capability of the terminal device, overheads for the bit width ofthe RI are relatively low.

For example, based on the fact that the bit information for RI reportingis 4 bits and the bit information for CRI reporting is 2 bits, the bitinformation for CRI and RI reporting is 6 bits. For example, meanings ofbit values of the RI and the CRI are as follows:

When the CRI=0 or 1, 0000 indicates that the RI=1, 0001 indicates thatthe RI=2, and so on.

When the CRI=2, {RI 1, RI 2}={1, 1}, {1, 2}, {2, 1}, {2, 2}, {2, 3}, {3,2}{3, 3}, {3, 4}, {4, 3}, and {4, 4}. 0000 indicates that {RI 1, RI2}={1, 1}, 0001 indicates that {RI 1, RI 2}={1, 2}, and so on.

It should be noted that, a predefined value of at least one of the bitinformation for CRI reporting, the bit information for CRI and RIreporting, and the bit information for RI reporting in this embodimentis not limited to the predefined value described above, or may beanother predefined value.

-   -   Manner 2: The network device determines at least one of the bit        information for CRI reporting, the bit information for CRI and        RI reporting, and the bit information for RI reporting, and        notifies the terminal device of the determined bit information.

For example, the network device sends at least one of the bitinformation for CRI reporting, the bit information for CRI and RIreporting, and the bit information for RI reporting to the terminaldevice by using higher layer signaling. The signaling may be radioresource control (RRC) signaling or media access control (MAC)signaling. In the LTE communications system, the signaling may be inconfiguration information of a CSI process, or signaling for CQIreporting, or another signaling field. This is not limited in thisembodiment. In the NR communications system, the signaling may be inconfiguration information of a reporting setting or another signalingfield. This is not limited in this embodiment.

For example, an index may be notified, and the index corresponds to atleast one of values of the bit information for CRI reporting, the bitinformation for CRI and RI reporting, and the bit information for RIreporting. For example, the index is 1, and corresponds to at least oneof the bit information for CRI reporting that includes 2 bits, the bitinformation for RI reporting that includes 4 bits, or the bitinformation for CRI and RI reporting that includes 6 bits. For example,the index is 2 and corresponds to at least one of the bit informationfor CRI reporting that includes 1 bit, the bit information for RIreporting that includes 3 bits, or the bit information for CRI and RIreporting that includes 4 bits. When the index is another value, theindex may further correspond to another case. This is not specificallylimited herein.

In one embodiment, a manner in which the network device determines atleast one of the bit information for CRI reporting, the bit informationfor CRI and RI reporting, and the bit information for RI reporting maybe predefined in a protocol, or may be determined based on a presetrule.

-   -   Manner 3: The terminal device determines, based on a preset        rule, at least one of the bit information for CRI reporting, the        bit information for CRI and RI reporting, and the bit        information for RI reporting included in the CSI feedback        related information, and the network device determines, based on        a preset rule that is the same as that used by the terminal        device, at least one of the bit information for CRI reporting,        the bit information for CRI and RI reporting, and the bit        information for RI reporting.

The terminal device may determine the bit width of the CRI and/or thebit width of the RI based on the second indication information and atleast one of a quantity of NZP CSI-RS resources, a quantity of antennaports for an NZP CSI-RS, capability information of the terminal device,or the value of the CRI. In an example, the bit width of the RI may bedetermined based on the second indication information and the quantityof antenna ports and/or the capability information of the terminaldevice. In the second implementation, the bit width of the RI isdetermined based on the second indication information and the quantityof antenna ports and/or the capability information of the terminaldevice, without considering the value of the CRI. For example, theCRI=0, the CRI=1, and the CRI=2 are not distinguished.

An example in which more than one NZP CSI-RS resource is configured isused to describe determining the bit width of the RI based on the secondindication information and a quantity of antenna ports and/or capabilityinformation of the terminal device.

Method 2.1: The bit width of the RI is determined based on the secondindication information and whether the quantity of antenna ports is 1.

In the following description process, when the quantity of antenna portsis used, only two cases in which the quantity of antenna ports is 1 andthe quantity of antenna ports is greater than 1 are distinguished.

In the present disclosure, when more than one NZP CSI-RS resource isconfigured, if there is no special description about an NZP CSI-RSresource to which the quantity of antenna ports corresponds, thequantity of antenna ports may be a maximum value of quantities ofantenna ports corresponding to the more than one configured NZP CSI-RSresource.

For example, if the quantity of antenna ports is 1, it indicates thatthe maximum value of the quantities of antenna ports corresponding tothe more than one configured NZP CSI-RS resource is 1, that is, aquantity of antenna ports corresponding to each NZP CSI-RS resourceis 1. If the quantity of antenna ports is greater than 1, it indicatesthat the maximum value of the quantities of antenna ports correspondingto the more than one configured NZP CSI-RS resource is greater than 1,that is, a quantity of antenna ports for at least one NZP CSI-RSresource is greater than 1.

Specifically, when the quantity of antenna ports is 1, the RI is not fedback. When the quantity of antenna ports is greater than 1, a value ofthe bit width of the RI is specified, for example, 4.

That is, in this embodiment of the present disclosure, the terminal maydetermine, based on the second indication information and the quantityof antenna ports that is 1, not to feed back the RI, and feed back onlythe CRI. The terminal may determine, based on the second indicationinformation and the quantity of antenna ports that is greater than 1,the bit width of the RI, for example, 4. The value of 4 of the bit widthis merely an example, and another value is also feasible. This is notspecifically limited herein.

In addition, for Manner 3, a more detailed solution is further provided.

Method 2.2: The bit width of the RI is determined based on the secondindication information and at least one of a quantity of antenna portsfor an NZP CSI-RS resource and the capability information of theterminal device (which is referred to as the capability of the terminaldevice for short).

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width of anRI used when a single RI is reported and/or determining a total quantityof bits occupied by a plurality of RIs (or an RI combination) when theplurality of RIs (or the RI combination) are reported. This is notspecifically limited herein.

This embodiment may be independently implemented, or may be applied incombination with another embodiment. This is not specifically limitedherein.

Specifically, for example, when the quantity of antenna ports for an NZPCSI-RS resource is 1, the RI is not fed back. When the quantity ofantenna ports for an NZP CSI-RS resource is greater than 1, the bitwidth of the RI may be determined based on the second indicationinformation and at least one of the quantity of antenna ports and thecapability of the terminal device. For example, when the secondindication information is configured and the quantity of antenna portsis 2 and/or the capability of the terminal device is that a supportedmaximum layer quantity is 2, the bit width of the RI is 2, or when thesecond indication information is configured and the quantity of antennaports for an NZP CSI-RS resource is 4 and/or the capability of theterminal device is that a supported maximum layer quantity is 4, the bitwidth of the RI is 4.

In one embodiment, in this embodiment of the present disclosure, if aplurality of CSI-RS resources are configured, when the bit width of theRI is determined, the quantity of antenna ports for an NZP CSI-RSresource that is based on may be a maximum value of quantities ofantenna ports corresponding to the configured NZP CSI-RS resources. Forexample, two NZP CSI-RS resources are configured, a quantity of antennaports for one NZP CSI-RS resource is 2, and a quantity of antenna portsfor the other NZP CSI-RS resource is 4. In this case, the bit width ofthe RI is determined based on the quantity of antenna ports that is 4. Aquantity of antenna ports corresponding to a resource may be understoodas a quantity of antenna ports used to transmit the resource.

The preset rule mentioned in Manner 2 or Manner 3 may be one or more ofthe following preset rules, and a specific preset rule or specificpreset rules may be predefined in a protocol. In this case, the networkdevice and/or the terminal device may have a corresponding configurationbased on a definition of the protocol, or may perform determining basedon specific implementation, or the terminal device may be notified, byusing signaling, of a preset rule for determining, for example, by usinghigher layer information or a physical layer channel such as RRCsignaling or MAC signaling. This is not specifically limited herein.

-   -   Preset rule 1: At least one of the bit information for CRI        reporting, the bit information for CRI and RI reporting, and the        bit information for RI reporting is determined based on a        maximum bit width of the CRI and the RI.

For the bit information for CRI reporting, an example in which two NZPCSI-RSs (the first NZP CSI-RS resource and the second NZP CSI-RSresource) are configured is used. To measure CSI in a plurality oftransmission modes, the value and a meaning of the CRI may be specified.

How to determine the bit width of the CRI and/or the bit meaning of theCRI is described below. Determining of the bit width of the CRI and/orthe bit meaning of the CRI may be an independent embodiment, or may becombined with another embodiment. This is not specifically limitedherein.

Determining method A: The bit width of the CRI and/or the bit meaning ofthe CRI are/is determined based on the second indication information.

Specifically, the terminal determines the bit width of the CRI based onthe second indication information, and/or the terminal determines thebit meaning of the CRI based on the second indication information.

For example, when the terminal receives the second indicationinformation, and FeCoMP-based CSI feedback is enabled, for example, whenthe second indication information is set to FeCoMPCSIEnabled or thevalue of FeCoMPCSIEnabled is TRUE, the terminal may determine the bitwidth of the CRI, for example, the bit width of the CRI is 2. Whendetermining to enable FeCoMP-based CSI feedback for the terminal, thebase station sends the second indication information, and determinesthat the bit width of the CRI of the terminal is 2. Herein, the bitwidth of the CRI that is 2 is merely an example, and another value isalso feasible. This is not specifically limited.

For example, when the terminal receives the second indicationinformation, and FeCoMP-based CSI feedback is enabled, for example, whenthe second indication information is set to FeCoMPCSIEnabled or thevalue of FeCoMPCSIEnabled is TRUE, the terminal may determine the bitmeaning of the CRI. For example, the bit meaning when the bit width ofthe CRI is 2 is specifically as follows: For example, 00 represents thatthe CRI=0, indicating that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource; 01 represents that the CRI=1,indicating that reported CSI is obtained through measurement based onthe second NZP CSI-RS resource; and 11 represents that reported CSI isobtained through measurement based on the first NZP CSI-RS resource andthe second NZP CSI-RS resource. When determining to enable FeCoMP-basedCSI feedback, the base station sends the first indication information,and determines that the bit width of the CRI of the terminal is 2 and/ordetermines the bit meaning of the CRI. Herein, the bit width of the CRIthat is 2 is merely an example, and another value is also feasible. Thisis not specifically limited.

In one embodiment, when the terminal does not receive the secondindication information, for example, when the second indicationinformation is not set to FeCoMPCSIEnabled or the value ofFeCoMPCSIEnabled is FALSE, the bit width of the CRI may be determinedbased on the prior art, for example, determined based on a quantity K ofconfigured NZP CSI-RS resources. For example, the bit width of the CRIis ┌log₂(K)┐. K is a positive integer, and ┌ ┐ represents rounding up.

Determining method B: The bit width of the CRI and/or the bit meaning ofthe CRI are/is determined based on the second indication information andat least one of a quantity of NZP CSI-RS resources, a quantity ofantenna ports for an NZP CSI-RS, capability information of the terminaldevice, or the value of the CRI.

In an example, the bit width of the CRI and/or the bit meaning of theCRI may be determined based on the second indication information and thequantity K of configured NZP CSI-RS resources.

Specifically, when the second indication information is set toFeCoMPCSIEnabled or the value of FeCoMPCSIEnabled is TRUE, the bit widthof the CRI is determined based on the quantity of configured NZP CSI-RSresources. For example, if the quantity of configured NZP CSI-RSresources is 2, the bit width of the CRI is 2. When the secondindication information is not set to FeCoMPCSIEnabled or the value ofFeCoMPCSIEnabled is FALSE, the bit width of the CRI is determined basedon the quantity K of configured NZP CSI-RS resources. For example, thebit width of the CRI is ┌log₂(K)┐. For example, if the quantity K ofconfigured NZP CSI-RS resources is 2, the bit width of the CRI is 1.

In this embodiment of the present disclosure, a relationship between thequantity of configured NZP CSI-RS resources and the bit width of the CRIand/or the bit meaning of the CRI may include at least one of thefollowing:

-   -   1. In coordinated multipoint transmission/reception (or FeCoMP        or hybrid transmission mode or non-coherent transmission        mode)-based CSI measurement and/or feedback, when the quantity        of NZP CSI-RS resources is K, the bit width of the CRI may be        ┌log₂(K+C_(K) ²)┐.

For example, four NZP CSI-RS resources are configured, and incoordinated multipoint transmission/reception (or FeCoMP or hybridtransmission mode or non-coherent transmission mode)-based CSImeasurement and/or feedback, four cases may be included in a single-cellscenario. In a coordinated multipoint transmission/reception scenario orFeCoMP, any two resources are selected from the four NZP CSI-RSresources. To be specific, there may be C_(K) ² cases. Therefore, theCRI needs to indicate a total of K+C_(K) ², cases. That is, the bitwidth of the CRI may be ┌log₂(K+C_(K) ²)┐. K is the quantity of NZPCSI-RS resources.

For example, K=4. In this case, a total of 4 bits are needed to indicatethe value of the CRI. In this case, the bit meaning of the CRI may be atleast one of the following, and a decimal system is used below torepresent the value of the CRI. It may be understood that the value ofthe CRI may also be represented by using a binary, octal, or hexadecimalsystem. The value in this embodiment of the present disclosure isrepresented by using one number system, but is not limited to theenumerated number system:

The CRI=0 indicates that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource.

The CRI=1 indicates that reported CSI is obtained through measurementbased on the second NZP CSI-RS resource.

The CRI=2 indicates that reported CSI is obtained through measurementbased on the third NZP CSI-RS resource.

The CRI=3 indicates that reported CSI is obtained through measurementbased on the fourth NZP CSI-RS resource.

The CRI=4 indicates that reported CSI is obtained through measurementbased on the first and second NZP CSI-RS resources.

The CRI=5 indicates that reported CSI is obtained through measurementbased on the first and third NZP CSI-RS resources.

The CRI=6 indicates that reported CSI is obtained through measurementbased on the first and fourth NZP CSI-RS resources.

The CRI=7 indicates that reported CSI is obtained through measurementbased on the second and third NZP CSI-RS resources.

The CRI=8 indicates that reported CSI is obtained through measurementbased on the second and fourth NZP CSI-RS resources.

The CRI=9 indicates that reported CSI is obtained through measurementbased on the third and fourth NZP CSI-RS resources.

In the foregoing embodiment, the value or the bit meaning of the CRIindicates a meaning of CSI feedback. In one embodiment, the meaning ofCSI feedback may be indicated by using another piece of information, forexample, first feedback information. In other words, the first feedbackinformation is used to indicate the meaning of CSI feedback. The meaningof CSI feedback may be at least one of a CSI measurement result incoordinated multipoint transmission/reception, a measurement result insingle-cell transmission, or a CSI measurement result in FeCoMP.Alternatively, the meaning of CSI feedback may be at least one of thefirst CSI, the second CSI, the third CSI, or the fourth CSI. The firstCSI is obtained based on the interference power; the second CSI isobtained based on the interference that is obtained by using the presetalgorithm when the resource used for channel measurement is the same asthe resource used for interference measurement; the third CSI isobtained based on the interference power and the interference that isobtained by using the preset algorithm when the resource used forchannel measurement is the same as the resource used for interferencemeasurement; and the fourth CSI is obtained based on the inter-streaminterference or the inter-codeword interference.

For example, the terminal may feed back the first feedback information.The first feedback information is used to indicate the meaning of CSIfeedback. According to the method, the base station may determine, byreceiving the first feedback information, a meaning of CSI feedback thatcorresponds to received CSI. The implementation may be an independentembodiment, or may be combined with another embodiment. This is notspecifically limited herein.

In this embodiment of the present disclosure, when the terminal receivesthe second indication information, where the second indicationinformation instructs to enable coordinated multipointtransmission/reception (or FeCoMP or hybrid transmission mode ornon-coherent transmission mode)-based CSI measurement and/or feedback,the terminal determines, based on the second indication information andthe quantity of NZP CSI-RS resources, that the bit width of the CRI is┌log₂(K+C_(K) ²)┐. Similarly, for a base station side, when determiningto enable FeCoMP-based CSI feedback for the terminal, the base stationsends the second indication information, and determines that the bitwidth of the CRI of the terminal is ┌log₂(K+C_(K) ²)┐. K is the quantityof NZP CSI-RS resources.

When the terminal does not receive the second indication information,that is, coordinated multipoint transmission/reception (or FeCoMP orhybrid transmission mode or non-coherent transmission mode)-based CSImeasurement and/or feedback are/is not enabled, for example, when normalmeasurement and feedback or single-cell measurement and feedback areperformed, when the quantity of NZP CSI-RS resources is K, the bit widthof the CRI may be ┌log₂(K)┐. K is a positive integer, and

$C_{K}^{2} = {\frac{K \times \left( {K - 1} \right)}{2}.}$

-   -   2. In coordinated multipoint transmission/reception (or FeCoMP        or hybrid transmission mode or non-coherent transmission        mode)-based CSI measurement and feedback, when the quantity of        NZP CSI-RS resources is K, the bit width of the CRI may be        ┌log₂(K+C_(K-1) ¹)┐ or another specified bit width, or is        calculated based on another specified calculation formula. This        is not specifically limited herein.

For example, K=4. In this case, a total of 3 bits are needed to indicatethe value of the CRI. In this case, the bit meaning of the CRI may be atleast one of the following, and a decimal system is used below torepresent the value of the CRI. It may be understood that the value ofthe CRI may also be represented by using a binary, octal, or hexadecimalsystem. The value in this embodiment of the present disclosure isrepresented by using one number system, but is not limited to theenumerated number system:

The CRI=0 indicates that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource.

The CRI=1 indicates that reported CSI is obtained through measurementbased on the second NZP CSI-RS resource.

The CRI=2 indicates that reported CSI is obtained through measurementbased on the third NZP CSI-RS resource.

The CRI=3 indicates that reported CSI is obtained through measurementbased on the fourth NZP CSI-RS resource.

The CRI=4 indicates that reported CSI is obtained through measurementbased on the first and second NZP CSI-RS resources.

The CRI=5 indicates that reported CSI is obtained through measurementbased on the first and third NZP CSI-RS resources.

The CRI=6 indicates that reported CSI is obtained through measurementbased on the first and fourth NZP CSI-RS resources.

During normal measurement such as single-cell measurement and feedback,when the quantity of NZP CSI-RS resources is K, the bit width of the CRImay be ┌log₂(K)┐.

Example 1: For example, the CRI=0 indicates that the first NZP CSI-RSresource has the optimal transmission performance. In this case, theforegoing case may correspond to a DPS transmission mode. The CRI=1indicates that the second NZP CSI-RS resource has the optimaltransmission performance. In this case, the foregoing case maycorrespond to the DPS transmission mode. The CRI=2 indicates that jointtransmission of the first NZP CSI-RS and the second NZP CSI-RS has theoptimal performance. In this case, the foregoing case may correspond tothe coordinated multipoint transmission/reception mode. When the valueof the CRI is 0, 1, or 2, the maximum bit width of the CRI is 2.

Example 2: The CRI=3 and the CRI=4 are added based on Example 1 in whichthe CRI=0, 1, or 2. The CRI=3 indicates that the first NZP CSI-RSresource has the optimal transmission performance, and there is nointerference to a transmission point corresponding to the second NZPCSI-RS resource. In this case, the foregoing case may correspond to atransmission mode of DPS+DPB. The CRI=4 indicates that the second NZPCSI-RS resource has the optimal transmission performance, and there isno interference to a transmission point corresponding to the first NZPCSI-RS resource. In this case, the foregoing case may correspond to thetransmission mode of DPS+DPB. When the value of the CRI is 0, 1, 2, 3,or 4, the maximum bit width of the CRI is 3.

The bit information for RI reporting may be determined based on amaximum bit width of the RI in one or more of the following manners. Aspecific manner or specific manners to be used may be specified based ona protocol or determined based on specific implementation.

-   -   Manner 1: In the LTE communications system, in the single-point        transmission mode, because a maximum layer quantity supported by        all terminal devices is 8, a maximum bit width for RI reporting        for one piece of CSI is 3, that is, the bit information for RI        reporting is 3 bits.    -   Manner 2: The maximum bit width of the RI is determined based on        a maximum quantity of antenna ports for a configured NZP CSI-RS        resource. For example, if the maximum quantity of antenna ports        is 1, the maximum bit width of the RI is 1, that is, the bit        information for RI reporting is 1 bit. For another example, if        the quantity of antenna ports is 2 or 4, the maximum bit width        of the RI is 2, that is, the bit information for RI reporting is        2 bits. For another example, if the maximum quantity of antenna        ports is 8, the maximum bit width of the RI is 3, that is, the        bit information for RI reporting is 3 bits.    -   Manner 3: The maximum bit width of the RI is determined based on        a maximum layer quantity supported by a terminal device that        performs CSI measurement and feedback. For example, if the        supported maximum layer quantity is 1, the maximum bit width of        the RI is 1, that is, the bit information for RI reporting is 1        bit. For another example, if the supported layer quantity is 2        or 4, the maximum bit width of the RI is 2, that is, the bit        information for RI reporting is 2 bits. For another example, if        the supported maximum layer quantity is 8, the maximum bit width        of the RI is 3, that is, the bit information for RI reporting is        3 bits.    -   Manner 4: When a plurality of RIs need to be reported in the        coordinated multipoint transmission/reception mode, a maximum        bit width of an RI corresponding to each NZP CSI-RS resource may        be calculated for the resource, to obtain the maximum bit width        of each RI, and then the maximum bit quantities of the RIs are        added to obtain the bit information for RI reporting.

If there are a plurality of CSI-RS resources, a maximum quantity ofantenna ports for these resources is determined as a quantity of antennaports that is related to the RI. Another method for determining thequantity of antenna ports that is related to the RI is further describedbelow. This embodiment may be used as an independent embodiment, or maybe combined with another embodiment. This is not specifically limitedherein. It may be understood that a more detailed determining method isdescribed below:

For coordinated multipoint transmission/reception mode (or FeCoMP orhybrid transmission mode or non-coherent transmission mode)-based CSImeasurement and/or feedback, the bit width of the RI is determined basedon a quantity of antenna ports for each CSI-RS resource.

In one embodiment, when a quantity of antenna ports for one CSI-RSresource is 1, and a quantity of antenna ports for another CSI-RSresource is M, the bit width of the RI may be 1 or ┌log₂ M┐. Whether aspecific bit width of the RI is 1 or ┌log₂ M┐ may be predefined in aprotocol, or notified by the base station by using signaling. This isnot specifically limited herein.

For example, there are two CSI-RS resources, a quantity of antenna portsfor one CSI-RS resource is 1, and a quantity of antenna ports for theother CSI-RS resource is M, where M is greater than 1. In this case, thebit width of the RI may be 1 or ┌log₂ M┐.

When the bit width of the RI is 1, the 1 bit may be used to respectivelyindicate two values of the RI (or an RI combination) when the CRI=0, 1,or 2. For example, the RI=1 or 2 when the CRI=0 or 1 and the RI={1, 1}or {1, 2} when the CRI=2 are supported.

When the bit width of the RI is ┌log₂ M┐, the ┌log₂ M┐ bits may be usedto respectively indicate M values of the RI (or an RI combination) whenthe CRI=0, 1, or 2. For example, the RI=1, 2, . . . , or M when theCRI=0 is supported, the RI=1, 2, . . . , or M when the CRI=1 issupported, and the RI={1, 1}, {1, 2}, . . . , or {1, M} when the CRI=2is supported.

In one embodiment, when a quantity of antenna ports for one CSI-RSresource is M1, and a quantity of antenna ports for at least one CSI-RSresource is M2, the bit width of the RI may be a maximum bit width ofthe RI in consideration of various values of the CRI.

Specifically, the terminal and/or the base station may determine themaximum bit width of the RI in the case of various values of the CRIbased on a bit width of the RI that corresponds to each CSI-RS resource,and then determine the bit width of the RI that is fed back.

For example, there are two CSI-RS resources, a quantity of antenna portsfor one CSI-RS resource is 2, and a quantity of antenna ports for theother CSI-RS resource is 4. In this case, the bit width of the RI may be2 or 3, which meets the maximum bit width of the RI in the case ofvarious values of the CRI. Whether a specific bit width of the RI is 2or 3 may be predefined in a protocol, or notified by the base station byusing signaling. This is not specifically limited herein.

A Case in which the Bit Width of the RI is 2:

When a quantity of antenna ports for the first CSI-RS resource is 2, andCSI corresponding to the first CSI-RS resource is fed back (for example,the CRI=0), a corresponding RI needs to be fed back by using 1 bit, andthe 1 bit may be used to indicate that the RI=1 or 2. An example inwhich a quantity of antenna ports for the second CSI-RS resource is 4 isused. When CSI corresponding to the second CSI-RS resource is fed back(for example, the CRI=1), a corresponding RI needs to be fed back byusing 2 bits, and the 2 bits may be used to indicate that the RI=1, 2,3, or 4. When CSI corresponding to the first CSI-RS resource and CSIcorresponding to the second CSI-RS resource are fed back (for example,the CRI=2), corresponding RIs need to be fed back by using 2 bits, andthe 2 bits may be used to indicate that the RIs={1, 1}, {1, 2}, {2, 1},or {2, 3}. Therefore, in consideration of the maximum bit width of theRI in the case of various values of the CRI, it may be determined thatthe bit width for RI feedback is 2 bits. For example, the RI=1 or 2 whenthe CRI=0, the RI=1, 2, 3, or 4 when the CRI=1, and {1, 1}, {1, 2}, {2,1}, or {2, 3} when the CRI=2 are supported.

A case in which the bit width of the RI is 3:

When a quantity of antenna ports for the first CSI-RS resource is 2, andCSI corresponding to the first CSI-RS resource is fed back (for example,the CRI=0), a corresponding RI needs to be fed back by using 1 bit, andthe 1 bit may be used to indicate that the RI=1 or 2. An example inwhich a quantity of antenna ports for the second CSI-RS resource is 4 isused. When CSI corresponding to the second CSI-RS resource is fed back(for example, the CRI=1), a corresponding RI needs to be fed back byusing 2 bits, and the 2 bits may be used to indicate that the RI=1, 2,3, or 4. When CSI corresponding to the first CSI-RS resource and CSIcorresponding to the second CSI-RS resource are fed back (for example,the CRI=2), corresponding RIs need to be fed back by using 3 bits, andthe 3 bits may be used to indicate that the RIs={1, 1}, {1, 2}, {2, 1},{2, 3}, {1, 3}, {1, 4}, or {2, 4}. Therefore, in consideration of themaximum bit width of the RI in the case of various values of the CRI, itmay be determined that the bit width for RI feedback that is 3 bits canbe supported. For example, the RI=1 or 2 when the CRI=0, the RI=1, 2, 3,or 4 when the CRI=1, and {1, 1}, {1, 2}, {2, 1}, {2, 3}, {1, 3}, {1, 4},or {2, 4} when the CRI=2 are supported.

-   -   Manner 5: When a plurality of RIs need to be combined and        reported in the coordinated multipoint transmission/reception        mode, the bit information for RI reporting may be determined        based on a quantity of combinations supported for combination        and reporting of the plurality of RIs. For example, when the RI        1 and the RI 2 are combined for reporting, {RI 1, RI 2}={1, 1},        {1, 2}, {2, 1}, {2, 2}, {2, 3}, {3, 2}{3, 3}, {3, 4}, {4, 3}, or        {4, 4}, that is, the quantity of combinations supported for RI        combination and reporting is 10. In this case, the bit        information for RI reporting is 4 bits. For another example,        when the RI 1 and the RI 2 are combined for reporting, {RI 1, RI        2}={1, 1}, {1, 2}, {2, 1}, {2, 2}, {2, 3}, {3, 2}, {1, 4}, {4,        1}, {3, 3}, {2, 4114, 2}, {1, 5}, {5, 1}, {3, 4}, {4, 3}, {2,        5}, {5, 2}, {4, 4}, {3, 5}, {5, 3}, {2, 6}, or {6, 2}, that is,        the quantity of combinations supported for RI combination and        reporting is 22. In this case, the bit information for RI        reporting is 5 bits. For another example, when the RI 1 and the        RI 2 are combined for reporting, {RI 1, RI 2}=at least one of        {1, 0}, {0, 1}, {2, 0}, {0, 2}, {3, 0}, {0, 3}, {4, 0}, {0, 4},        {5, 0}, {0, 5}, {6, 0}, {0, 6}, {7, 0}, {0, 7}, {7, 0}, {0, 7},        {8, 0}, {0, 8}, {1, 1}, {1, 2}, {2, 1}, {2, 2}, {2, 3}, {3, 2},        {1, 4}, {4, 1}, {3, 3}, {2, 4114, 2}, {1, 5}, {5, 1}, {3, 4},        {4, 3}, {2, 5}, {5, 2}, {4, 4}, {3, 5}, {5, 3}, {2, 6}, {6, 2},        {7, 1}, or {1, 7}. For example, when some of the values are        selected, when the quantity of combinations supported for RI        combination and reporting is 22, the bit information for RI        reporting is 5 bits.

After the bit information for CRI reporting and the bit information forRI reporting are determined by using Preset rule 1, the bit informationfor CRI and RI reporting may be equal to a sum of the bit informationfor CRI reporting and the bit information for RI reporting.

-   -   Preset rule 2: At least one of the bit information for CRI        reporting, the bit information for CRI and RI reporting, and the        bit information for RI reporting is determined in consideration        of both the CRI and the RI. An example is used below for        description.

When DPS is considered for feedback, when the CRI=0, the maximum bitwidth for RI reporting may be determined based on the quantity ofantenna ports for the first NZP CSI-RS resource, for example, themaximum bit width of the RI is 3. When the CRI=1, the maximum bit widthfor RI reporting may be determined based on the quantity of antennaports for the second NZP CSI-RS resource, for example, the maximum bitwidth for RI reporting is 2. Therefore, for Case 1 for the CRI, the bitinformation for CRI reporting is 1 bit, the bit information for RIreporting is 3 bits, and the bit information for CRI and RI reporting is4 bits.

When the DPS and coordinated multipoint transmission/reception modes areconsidered for feedback, the CRI=2 is added based on the fact that onlythe CRI=0 or 1 is considered in DPS for feedback above. When the CRI=2,the maximum bit width for RI reporting may be determined based on thequantity of antenna ports for the first NZP CSI-RS resource and thequantity of antenna ports for the second NZP CSI-RS resource. Forexample, a plurality of RIs are independently reported or a plurality ofRIs are combined for reporting. In this case, it is assumed that themaximum bit width for RI reporting is 4. Therefore, for Case 2 for theCRI, the bit information for CRI reporting is 2 bits, the bitinformation for RI reporting is 4 bits, and the bit information for CRIand RI reporting is 6 bits.

When the DPS, DPB, and coordinated multipoint transmission/receptionmodes are considered for feedback, the CRI=3 or 4 is added based on thefact that only the CRI=0, 1, or 2 is considered in the DPS andcoordinated multipoint transmission/reception modes for feedback above.When the CRI=3, the maximum bit width for RI reporting may be determinedbased on the quantity of antenna ports for the first NZP CSI-RSresource, and it is assumed that the maximum bit width for RI reportingis 2. When the CRI=4, the maximum bit width for RI reporting may bedetermined based on the quantity of antenna ports for the second NZPCSI-RS resource, and it is assumed that the maximum bit width for RIreporting is 2. Therefore, for Case 3 for the CRI, the bit informationfor CRI reporting is 3 bits, the bit information for RI reporting is 4bits, and the bit information for CRI and RI reporting is 7 bits.

-   -   Preset rule 3: In the NR communications system, at least one of        the bit information for CRI reporting, the bit information for        CRI and RI reporting, and the bit information for RI reporting        may be determined based on a quantity of links or a quantity of        measurement channels.

For example, if the quantity of links or the quantity of measurementchannels is 2, for a value of the bit information of the CRI, there maybe three cases. For example, when the CRI=0, it indicates that CSIobtained through measurement based on an NZP CSI-RS resourcecorresponding to the first link or a link of the first measurementchannel has the optimal performance. For example, when the CRI=1, itindicates that CSI obtained through measurement based on an NZP CSI-RSresource corresponding to the second link or a link of the secondmeasurement channel has the optimal performance. For example, when theCRI=2, it indicates that CSI obtained through measurement based on jointtransmission of an NZP CSI-RS resource corresponding to the first linkor a link of the first measurement channel and an NZP CSI-RS resourcecorresponding to the second link or a link of the second measurementchannel has the optimal performance. In this case, there may be 2 bitsfor CRI reporting.

For another example, if the quantity of links or the quantity ofmeasurement channels is 3, for a value of the bit information of theCRI, there may be three cases. For example, when the CRI=0, it indicatesthat CSI obtained through measurement based on an NZP CSI-RS resourcecorresponding to the first link or a link of the first measurementchannel has the optimal performance. For example, when the CRI=1, itindicates that CSI obtained through measurement based on an NZP CSI-RSresource corresponding to the second link or a link of the secondmeasurement channel has the optimal performance. For example, when theCRI=2, it indicates that CSI obtained through measurement based on anNZP CSI-RS resource corresponding to the third link or a link of thethird measurement channel has the optimal performance. In this case,there may be 2 bits for CRI reporting.

A value of the bit information of the RI may be determined based on aquantity of antenna ports for an NZP CSI-RS resource corresponding toeach link. There may be another determining manner. This is not limitedherein.

In this embodiment, the CSI fed back by the terminal device includesinformation used to indicate a resource with better transmissionperformance (that is, CSI obtained in which measurement behavior is fedback), which may be the same as or different from that in the prior art.Descriptions are provided below. In this embodiment, this part may beused in combination with another part, or may be independently applied,to provide a CSI feedback method. In the prior art, the CRI fed back inthe single-point transmission mode is a CSI-RS resource indication, usedto indicate a resource with better transmission performance. In thecoordinated multipoint transmission/reception mode, the CRI is used toindicate a resource with better transmission performance or indicate aplurality of resources with better joint transmission performance.

In this embodiment, one or more of a resource setting index, a resourceset index, and a resource index may be fed back to indicate a resourcewith better transmission performance or indicate a plurality ofresources with better joint transmission performance. Descriptions arerespectively provided below for different scenarios. A feedback index isa feedback indication, and one feedback index indicates a resourcetransmission indication in one definition. Specifically, the foregoingfeedback operation may be at least one of the following designs. Aspecific design or a combination of specific designs may be defined in aprotocol, or determined based on a system design:

Design 1: One reporting setting is associated with a plurality ofresource settings, one resource setting includes one resource set, andone resource set includes one channel measurement resource, or oneresource set includes one or more resources related to one CSImeasurement result. In this case, a feedback index corresponding to aresource setting index may be fed back to indicate a resource withbetter transmission performance or indicate a plurality of resourceswith better joint transmission performance.

A schematic diagram of a resource configuration for CSI shown in FIG.10A is used as an example. When a feedback index=2 is fed back, itindicates that a channel part of a CSI report that is fed back by theterminal device and that is in a measurement resource in a resourcesetting index=2 has better transmission performance. If the resourcesetting index=2 corresponds to one channel measurement resource, or aresource related to one CSI measurement result included in the resourcesetting index=2 includes one channel measurement resource, it indicatesthat transmission performance in the single-point transmission mode forthe resource is better. If the resource related to the CSI measurementresult corresponding to the resource setting index=2 includes more thanone channel measurement resource, it indicates that transmissionperformance in the coordinated multipoint transmission/reception modefor the plurality of resources is better. When a feedback index=1 and afeedback index=2 are fed back, it indicates that a channel part of a CSIreport that is fed back by the terminal device and that is in ameasurement resource in the resource setting index=1 and the resourcesetting index=2 has better transmission performance in the coordinatedmultipoint transmission/reception mode.

Design 2: One reporting setting is associated with a plurality ofresource settings, one resource setting includes one or more resourcesets, and one resource set includes one channel measurement resource, orone resource set includes one or more resources related to one CSImeasurement result. In this case, a feedback index corresponding to aresource setting index and a resource set index may be fed back toindicate a resource with better transmission performance or indicate aplurality of resources with better joint transmission performance. Amanner of feeding back the resource setting index and the resource setindex may use a joint indication or an independent indication. Aspecific feedback manner to be used may be configured by the networkdevice or predefined.

A schematic diagram of a resource configuration for CSI shown in FIG.10A is used as an example. When a feedback index=0110, it indicates thata channel part of a CSI report that is fed back by the terminal deviceand that is in a measurement resource in a resource set index=2 in aresource setting index=1 has better transmission performance. The firsttwo bits 01 in the feedback index=0110 indicates the resource settingindex, and the last two bits 10 in the feedback index=0110 indicates theresource set index. If the resource set index=2 in the resource settingindex=1 corresponds to one channel measurement resource, or a resourcerelated to one CSI measurement result corresponding to the resource setindex=2 in the resource setting index=1 includes one channel measurementresource, it indicates that transmission performance in the single-pointtransmission mode for the resource is better. If a resource related toone CSI measurement result corresponding to the resource set index=2 inthe resource setting index=1 includes more than one channel measurementresource, it indicates that transmission performance in the coordinatedmultipoint transmission/reception mode for the plurality of resources isbetter.

Design 3: One reporting setting is associated with a plurality ofresource settings, one resource setting includes one or more resourcesets, one resource set includes one or more channel measurementresources, or one resource set includes resources related to one or moreCSI measurement results, and a resource related to each CSI measurementresult may include one or more resources. In this case, a feedback indexcorresponding to a resource setting index, a resource set index, and aresource index is fed back to indicate a resource with bettertransmission performance or indicate a plurality of resources withbetter joint transmission performance. A manner of feeding back theresource setting index, the resource set index, and the resource indexmay use a joint indication or an independent indication, or two of thethree indexes may use a joint indication. A specific feedback manner tobe used and a specific mapping and encoding sequence may be configuredby the network device or predefined.

A schematic diagram of a resource configuration for CSI shown in FIG.10A is used as an example. When a feedback index=011001, it indicatesthat a channel part of a CSI report that is fed back by the terminaldevice and that is in a measurement resource in a resource index=1 in aresource set index=2 in a resource setting index=1 has bettertransmission performance. The first two bits 01 in the feedbackindex=011001 indicates the resource setting index, the two bits 10 inthe middle in the feedback index=011001 indicates the resource setindex, and the last two bits 10 in the feedback index=011001 indicatesthe resource index. If the resource index=1 in the resource set index=2in the resource setting index=1 corresponds to one channel measurementresource, or the resource index=1 in the resource set index=2 in theresource setting index=1 corresponds to a resource related to one CSImeasurement result, and the resource related to the CSI measurementresult includes one channel measurement resource, it indicates that thetransmission performance in the single-point transmission mode for theresource is better. If the resource index=1 in the resource set index=2in the resource setting index=1 corresponds to a resource related to oneCSI measurement result, and the resource related to the CSI measurementresult includes more than one channel measurement resources, or theresource index=1 in the resource set index=2 in the resource settingindex=1 corresponds to resources related to a plurality of (more thanone) CSI measurement results, and a resource related to each CSImeasurement result includes one or more channel measurement resources,it indicates that transmission performance in the coordinated multipointtransmission/reception mode for the plurality of resources is better.

Design 4: One reporting setting is associated with one resource setting,the resource setting includes one or more resource sets, and eachresource set includes one channel measurement resource, or each resourceset includes one or more resources related to one CSI measurementresult. In this case, a feedback index corresponding to a resource setindex is fed back to indicate a resource with better transmissionperformance or indicate a plurality of resources with better jointtransmission performance.

A schematic diagram of a resource configuration for CSI shown in FIG.10A is used as an example. When a feedback index=2 is fed back, itindicates that a channel part of a CSI report that is fed back by theterminal device and that is in a measurement resource in a resource setindex=2 has better transmission performance. If the resource set index=2corresponds to one channel measurement resource, or a resource relatedto one CSI measurement result corresponding to the resource set index=2includes one channel measurement resource, it indicates thattransmission performance in the single-point transmission mode for theresource is better. If the resource related to the CSI measurementresult corresponding to the resource set index=2 includes more than onechannel measurement resource, it indicates that transmission performancein the coordinated multipoint transmission/reception mode for theplurality of resources is better. When a resource set index=1 and aresource set index=2 are fed back, it indicates that a channel part of aCSI report that is fed back by the terminal device and that is in ameasurement resource in the resource set index=1 and the resource setindex=2 has better transmission performance in the coordinatedmultipoint transmission/reception mode.

Design 5: One reporting setting is associated with one resource setting,the resource setting includes one or more resource sets, each resourceset includes one or more channel measurement resources, or each resourceset includes resources related to one or more CSI measurement results,and there is one or more resources related to each CSI measurementresult. In this case, a feedback index corresponding to a resource setindex and a resource index is fed back to indicate a resource withbetter transmission performance or indicate a plurality of resourceswith better joint transmission performance. A manner of feeding back theresource set index and the resource index may use a joint indication oran independent indication.

Design 6: One reporting setting is associated with a plurality ofresource settings, each resource setting includes one resource set, theresource set includes one or more channel measurement resources, or theresource set includes resources related to one or more CSI measurementresults, and there is one or more resources related to each CSImeasurement result. A feedback index corresponding to a resource settingindex and a resource index is fed back to indicate a resource withbetter transmission performance or indicate a plurality of resourceswith better joint transmission performance.

In the foregoing six designs, when the resource setting index is fedback, a new feedback variable such as a resource set identifier(resource setting index, RSI) may be defined, or a name of a feedbackvariable for the CRI may continue to be used. When the resource setindex is fed back, a new feedback variable such as an RSI 1 may bedefined, or a name of a feedback variable for the CRI continues to beused. When the resource index is fed back, the CRI may be used. This isnot limited in this embodiment. A feedback manner and/or a mapping andencoding sequence used by the feedback index may be configured by thebase station or predefined. This is not limited in this embodiment.

Further, this embodiment of the present disclosure further provides anassumed scenario: the terminal device supports CSI measurement andfeedback in the hybrid mode, and supports CSI measurement and feedbackin the single-point transmission mode. In this scenario, based on Case2, to be specific, the network device determines that the terminaldevice needs to perform CSI measurement and feedback in the single-pointtransmission mode, the configuration information sent by the networkdevice to the terminal device meets at least one of the followingconditions (1) to (8), and the terminal device may learn, based on theconfiguration information in at least one of the following conditions(1) to (8), how to perform CSI measurement and feedback, that is, learnto perform CSI measurement and feedback in the single-point transmissionmode. It may be understood that, this part may be applied in combinationwith another part of this embodiment of the present disclosure, or maybe independently applied.

The conditions (1) to (8) are respectively as follows:

-   -   (1) The configuration information includes one NZP CSI-RS        resource of the class A.    -   (2) The configuration information includes M1 NZP CSI-RS        resources of the class B and the CSI measurement behavior        indication information and/or the CSI feedback related        information indication information, where M1 is an integer        greater than or equal to 1.

Alternatively, the configuration information includes M2 NZP CSI-RSresources of the class B, where M2 is an integer greater than or equalto 1. When the CSI measurement behavior indication information and theCSI feedback related information indication information are notconfigured, measurement and feedback in the single-point transmissionmode may also be predefined in a protocol.

-   -   (3) The configuration information includes the CSI measurement        behavior indication information and/or the CSI feedback related        information indication information.

In the foregoing conditions (2) and (3), the CSI measurement behaviorindication information indicates CSI measurement behavior in thesingle-point transmission mode, and the CSI feedback related informationindication information indicates CSI feedback related information in thesingle-point transmission mode. For example, the CSI measurementbehavior indication information instructs to measure at least one of thefirst CSI, the second CSI, and the third CSI, and the CSI feedbackrelated information indication information includes use of jointencoding for the CRI and the RI. Related explanations of the first CSI,the second CSI, and the third CSI are already described above, anddetails are not described herein again.

-   -   (4) The configuration information includes a QCL type of an        antenna port that is the type A or the type B.    -   (5) The configuration information includes a PQI that indicates        that a QCL quantity is equal to 1.    -   (6) The configuration information includes a PQI that indicates        that a parameter group quantity is equal to 1.    -   (7) The configuration information includes one reporting setting        associated with one channel link or one RS setting or one RS        set.    -   (8) The configuration information includes indication        information, where the indication information instructs the        terminal device to perform CSI measurement and feedback in the        single-point transmission mode. For example, the indication        information indicates that a current CSI process is a CSI        process in the single-point transmission mode, and the terminal        device learns, based on the indication information, to perform        CSI measurement and feedback in the single-point transmission        mode.

The determined CSI measurement behavior includes measurement of at leastone of the first CSI, the second CSI, and the third CSI. Relatedexplanations of the first CSI, the second CSI, and the third CSI arealready described above, and details are not described herein again.

The determined CSI feedback related information includes use of jointencoding for the CRI and the RI.

It should be noted that, based on Case 2, the network device determinesthat the terminal device needs to perform CSI measurement and feedbackin the single-point transmission mode. Related explanations anddescriptions may be based on Case 1, to be specific, the network devicedetermines that the terminal device needs to perform CSI measurement andfeedback in the hybrid mode. Details are not described herein again.

Further, this embodiment of the present disclosure further provides anassumed scenario: When the terminal device supports CSI measurement andfeedback in the coordinated multipoint transmission/reception mode, andsupports CSI measurement and feedback in the single-point transmissionmode, based on Case 3, to be specific, the network device determinesthat the terminal device needs to perform CSI measurement and feedbackin the coordinated multipoint transmission/reception mode, theconfiguration information sent by the network device to the terminaldevice needs to meet a particular condition. Specifically, theconfiguration information meets at least one of the following conditions(1) to (11), and the terminal device may learn, based on theconfiguration information in at least one of the following conditions(1) to (11), how to perform CSI measurement and feedback, that is, learnto perform CSI measurement and feedback in the coordinated multipointtransmission/reception mode. It may be understood that, this part may beapplied in combination with another part of this embodiment of thepresent disclosure, or may be independently applied.

The conditions (1) to (11) are respectively as follows:

-   -   (1) The configuration information includes N11 non-zero power        (non-zero power, NZP) CSI-RS resources of the class A, where N11        is a positive integer greater than or equal to 2.    -   (2) The configuration information includes N21 NZP CSI-RS        resources of the class B and the CSI measurement behavior        indication information and/or the CSI feedback related        information indication information, where N21 is a positive        integer greater than or equal to 2.

Alternatively, the configuration information includes N22 NZP CSI-RSresources of the class B, where N22 is an integer greater than or equalto 1. When the CSI measurement behavior indication information and theCSI feedback related information indication information are notconfigured, measurement and/or feedback in the coordinated multipointtransmission/reception mode may also be predefined in a protocol.

-   -   (3) The configuration information includes the CSI measurement        behavior indication information and/or the CSI feedback related        information indication information.

In the foregoing conditions (2) and (3), the CSI measurement behaviorindication information indicates CSI measurement behavior in thecoordinated multipoint transmission/reception mode, and the CSI feedbackrelated information indication information indicates CSI feedbackrelated information in the coordinated multipoint transmission/receptionmode. For example, the CSI measurement behavior indication informationinstructs to measure the fourth CSI, where the fourth CSI is obtainedbased on the inter-stream interference or the inter-codewordinterference, and the CSI feedback related information indicationinformation includes use of joint encoding or independent encoding forthe CRI and the RI.

-   -   (4) The configuration information includes a QCL type of an        antenna port that is the type C.    -   (5) The configuration information includes a QCL type of an        antenna port that is the type C and a CSI process quantity that        is 1.    -   (6) The configuration information includes a PQI that indicates        that a QCL quantity is greater than M3, where M3 is a positive        integer greater than or equal to 1.    -   (7) The configuration information includes a PQI that indicates        that a parameter group quantity is greater than P1, where P1 is        a positive integer greater than or equal to 1.    -   (8) The configuration information includes at least one of the        bit information for CRI reporting, the bit information for CRI        and RI reporting, and the bit information for RI reporting.

If bit information for CRI reporting, bit information for CRI and RIreporting, and bit information for RI reporting that are used when thenetwork device requires the terminal device to perform CSI measurementand feedback in the single-point transmission mode are predefinedvalues, the configuration information does not need to include at leastone of the bit information for CRI reporting, the bit information forCRI and RI reporting, and the bit information for RI reporting, so thatwhen the configuration information meets the condition (8), it may bedetermined that the network device requires the terminal device toperform CSI measurement and feedback in the coordinated multipointtransmission/reception mode, and the bit information included in theconfiguration information is bit information used when the terminaldevice performs CSI measurement and feedback in the coordinatedmultipoint transmission/reception mode. Otherwise, when theconfiguration information meets the condition (8), it is furtherdetermined, with reference to other information in the configurationinformation, that the network device requires the terminal device toperform CSI measurement and feedback in the coordinated multipointtransmission/reception mode.

-   -   (9) The configuration information includes that when the bit        information for CRI reporting is L and there are K NZP CSI-RS        resources, L≠┌log₂ K┐.    -   (10) The configuration information includes one reporting        setting that is associated with at least one of Q channel links,        T RS settings, and S RS sets, where Q is a positive integer        greater than or equal to 2, T is a positive integer greater than        or equal to 2, and S is a positive integer greater than or equal        to 2.    -   (11) The configuration information includes indication        information, where the indication information instructs the        terminal device to perform CSI measurement and feedback in the        coordinated multipoint transmission/reception mode. For example,        the indication information indicates that a current CSI process        is a CSI process in the coordinated multipoint        transmission/reception mode, and the terminal device learns,        based on the indication information, to perform CSI measurement        and feedback in the coordinated multipoint        transmission/reception mode.

The determined CSI measurement behavior includes measurement of thefourth CSI. The fourth CSI is obtained based on the inter-streaminterference or the inter-codeword interference.

The determined CSI feedback related information includes use of jointencoding or independent coding for the CRI and the RI and/or the mappingmode of mapping the CRI and the RI to the time-frequency resource.

It should be noted that, based on Case 3, the network device determinesthat the terminal device needs to perform CSI measurement and feedbackin the coordinated multipoint transmission/reception mode. Relatedexplanations and descriptions may be based on Case 1, to be specific,the network device determines that the terminal device needs to performCSI measurement and feedback in the hybrid mode. Details are notdescribed herein again.

It may be understood that, a specific one of the foregoing severalassumed scenarios that is to be used may be predefined in a protocol, ormay be determined based on system implementation, or may be notified bythe base station to the terminal by using signaling. This is notspecifically limited herein.

An embodiment of the present disclosure further provides acommunications method. FIG. 5-3 shows a procedure of interaction betweena terminal device and a network device in the communications method, andthe method includes the following operations.

Operation 511: The network device sends first indication information tothe terminal device, and the terminal device receives the firstindication information, where the first indication information is usedto enable further enhancements to coordinated multi-point (FeCoMP)-basedCSI feedback, or enable coordinated multipointtransmission/reception-based CSI feedback, or enable hybrid transmissionmode-based CSI feedback.

Operation 512: The terminal device determines CSI feedback relatedinformation based on the first indication information, where the CSIfeedback related information includes at least one of a coding schemefor a CRI and an RI, a bit width of a CRI, a bit width of an RI, a bitmeaning of a CRI, or a bit meaning of an RI.

This embodiment is described by using the network device as a basestation. All solutions may also be applied to a case in which thenetwork device is another network device. The network device and thebase station may be replaced with each other unless otherwise specified.The terminal device, a terminal, and UE may be replaced with each otherunless otherwise specified. This embodiment may be an independentembodiment, or may be combined with another embodiment of the presentdisclosure. This is not specifically limited herein. It should be notedthat, the numbers of the operations in this embodiment are merely usedto distinguish from the numbers of the operations in FIG. 5-1 , and itdoes not indicate that the operations in this embodiment are completedafter the operations shown in FIG. 5-1 .

That the first indication information is used to enable FeCoMP-based CSIfeedback, or enable coordinated multipoint transmission/reception-basedCSI feedback, or enable CSI feedback in a hybrid transmission mode maybe understood as that the first indication information is used to enableFeCoMP-based CSI measurement and/or feedback, or enable coordinatedmultipoint transmission/reception-based CSI measurement and/or feedback,or enable hybrid transmission mode-based CSI measurement and/orfeedback. It may also be understood that, the terminal device maydetermine CSI measurement behavior based on the first indicationinformation.

The enabling FeCoMP-based CSI feedback means that at least FeCoMP-basedCSI measurement and feedback are supported. For example, only CSImeasurement and feedback in FeCoMP are supported, or both CSImeasurement and feedback in FeCoMP and CSI measurement and feedback in asingle cell are supported.

The enabling coordinated multipoint transmission/reception-based CSImeasurement and/or feedback may be CSI measurement and/or feedback in atleast one of non-coherent joint transmission, coherent transmission, orother coordinated multipoint transmission/reception, or may be CSImeasurement and/or feedback based on another coordinated multipointtransmission/reception mode.

The enabling hybrid transmission mode-based CSI feedback means that CSImeasurement and/or feedback in at least two transmission modes are/issupported, for example, CSI measurement and/or feedback in FeCoMP and asingle cell, or CSI measurement and/or feedback in a single cell andcoordinated multipoint transmission/reception, or CSI measurement and/orfeedback based on any other two transmission modes.

CSI measurement (which may also be referred to as CSI measurementbehavior) and CSI feedback (which may also be referred to as CSIreporting) may be related.

Specifically, the bit width of the CRI and/or the bit width of the RImay be determined based on the CSI measurement behavior and the CSIfeedback related information.

The CSI measurement behavior may be FeCoMP-based CSI measurement.

FeCoMP-based CSI measurement may be understood as non-coherent jointtransmission (JT)-based measurement. FeCoMP-based measurement includes,for example, inter-stream interference measurement and normalmeasurement (for example, single-cell measurement). Specific examplesare as follows:

For one CSI process or one CSI measurement, the network deviceconfigures two NZP CSI-RS resources and one interference measurementresource (for example, a ZP CSI-RS resource) for the terminal device.FeCoMP-based CSI feedback may include the following cases:

If the CRI=0, it indicates that CSI reporting is specific to the firstNZP CSI-RS resource, and CSI reporting may be performed by using areporting method in the prior art.

If the CRI=1, it indicates that CSI reporting is specific to the secondNZP CSI-RS resource, and CSI reporting may be performed by using areporting method in the prior art.

If the CRI=2, it indicates that CSI reporting is specific to two NZPCSI-RS resources.

If the CRI=2, for the CSI process or the CSI measurement, the terminaldevice may calculate two CSI sets for two NZP CSI-RS resources. Each CSIset corresponds to one codeword. Specifically, the following method maybe used for calculation: For each NZP CSI-RS resource or codeword, theterminal device determines an RI and/or a PMI, and calculates a CQI ofeach resource or codeword. Inter-codeword or inter-resource interferenceneeds to be considered when the CQI is calculated. For example, theinter-codeword or inter-resource interference is obtained based onchannel measurement and precoding matrix of the other resource orcodeword in the two NZP CSI-RS resources. The precoding matrix may be aunit matrix, a measured PMI, or a PMI indicated by the base station.This is not specifically limited herein.

For example, if the CRI=2, a calculation method is as follows:

a  CQI  1 = H 1W 1/(H 2W 2 + I 1), and  a  CQI  2 = H 2W 2/(H 1W 1 + I 2).

H1 is a channel obtained through measurement by using the first NZPCSI-RS resource, W1 is a precoding matrix obtained through measurementby using the first NZP CSI-RS resource, H2 is a channel obtained throughmeasurement by using the second NZP CSI-RS resource, W2 is a precodingmatrix obtained through measurement by using the second NZP CSI-RSresource, and I1 and I2 are interference obtained by using aninterference measurement resource. Another calculation method is notlimited.

In one embodiment, in the foregoing example, FeCoMP-based CSImeasurement includes normal measurement (for example, single-cellmeasurement). For example, measurement performed when the CRI=0 andmeasurement performed when the CRI=1 are single-cell measurement. Inaddition, FeCoMP-based CSI measurement behavior may not include normalmeasurement (for example, single-cell measurement). This is notspecifically limited herein.

Normal measurement such as single-cell measurement in the presentdisclosure or a measurement and/or feedback method in the prior art maybe CSI measurement and/or feedback without considering interferencemeasurement that is performed by using an NZP (non zero power) CSI-RSresource. For example, only CSI measurement and/or feedback ininterference measurement that is performed by using a ZP (zero power)CSI-RS resource may be considered.

In this embodiment of the present disclosure, for example, the firstindication information may be implemented by using a parameterFeCoMPCSIEnabled. If the parameter exists (that is, the parameter isconfigured), or a value of the parameter is TRUE, it indicates that CSImeasurement behavior indicated by the first indication information isFeCoMP-based CSI measurement. If the parameter does not exist (that is,the parameter is not configured), or a value of the parameter is FALSE,it indicates that CSI measurement behavior indicated by the firstindication information is normal measurement that is not FeCoMP-basedCSI measurement. That the first indication information is used to enablefurther enhancements to coordinated multi-point (further enhancementCoMP, FeCoMP)-based CSI feedback, or enable coordinated multipointtransmission/reception-based CSI feedback, or enable hybrid transmissionmode-based CSI feedback may specifically mean that: if the parameter isconfigured, it indicates that further enhancements to coordinatedmulti-point (further enhancement CoMP, FeCoMP)-based CSI feedback isenabled, or coordinated multipoint transmission/reception-based CSIfeedback is enabled, or hybrid transmission mode-based CSI feedback isenabled. Alternatively, if the value of the parameter is TRUE, furtherenhancements to coordinated multi-point (further enhancement CoMP,FeCoMP)-based CSI feedback is enabled, or coordinated multipointtransmission/reception-based CSI feedback is enabled, or hybridtransmission mode-based CSI feedback is enabled.

In this embodiment of the present disclosure, the CSI feedback relatedinformation may include a CSI reporting mode, for example, periodicreporting or aperiodic reporting, or semi-persistent reporting, or maybe a reporting mode 1-0, 1-1, 2-0, 2-1, 2-2, 3-0, 3-1, or 3-2.

The CSI reporting mode may be a CSI reporting manner, for example, atleast one of periodic reporting, aperiodic reporting, or semi-staticreporting. Alternatively, the CSI reporting mode may be CSI reportingcontent, for example, at least one of CQI reporting, CQI and PMIreporting, wideband CQI reporting, subband CQI reporting, wideband PMIreporting, subband PMI reporting, UE selected subband reporting, or basestation-configured subband reporting. Alternatively, the CSI reportingmode may be a set of a CSI reporting manner and reporting content.

In one embodiment, CSI in the aperiodic CSI reporting mode may be fedback on a PUSCH (physical uplink shared channel), and CSI in theperiodic CSI reporting mode may be fed back on a PUCCH, or may be fedback on a PUSCH when both a PUCCH (physical uplink control channel) anda PUSCH exist.

The reporting mode may be similar to a reporting mode in LTE. A specificexample is as follows:

TABLE 1 CQI and PMI feedback types in a PUSCH CSI reporting mode PMIFeedback Type No Single Multiple PMI PMI PMIs PUSCH CQI Wideband CQIMode 1-0 Mode 1-1 Mode 1-2 feedback UE Selected Mode 2-0 Mode 2-2 typesubband CQI Higher Layer- Mode 3-0 Mode 3-1 Mode 3-2 configured subbandCQI feedback

As shown in the foregoing table, the reporting mode 1-0 refers towideband CQI reporting and no PMI feedback. The reporting mode 1-1refers to wideband CQI reporting and wideband PMI reporting. Thereporting mode 1-2 refers to wideband CQI reporting and subband PMIreporting. The reporting mode 2-0 refers to CQI reporting in UE selectedsubband CQI reporting and no PMI feedback. The reporting mode 2-2 refersto CQI reporting in UE selected subband CQI reporting and subband PMIreporting. The reporting mode 3-0 refers to CQI reporting in higherlayer-configured subband CQI reporting and no PMI feedback. Thereporting mode 3-1 refers to CQI reporting in higher layer-configuredsubband CQI reporting and wideband PMI reporting. The reporting mode 3-2refers to CQI reporting in higher layer-configured subband CQI reportingand subband PMI reporting.

In this embodiment of the present disclosure, there are twoimplementation possibilities for the reporting mode:

In the first possibility, the CSI measurement behavior is determinedwith reference to a reporting mode configuration. For example, ifFeCoMPCSIEnabled is configured or the value of FeCoMPCSIEnabled is TRUE,and the aperiodic reporting mode is configured, FeCoMP-based CSImeasurement and/or feedback are/is used. If FeCoMPCSIEnabled isconfigured or the value of FeCoMPCSIEnabled is TRUE, and the periodicreporting mode is configured, or if FeCoMPCSIEnabled is not configuredor the value of FeCoMPCSIEnabled is FALSE, measurement and/or feedbackare/is performed in a manner in the prior art.

In this possibility, when FeCoMPCSIEnabled is configured or the value ofFeCoMPCSIEnabled is TRUE, and the aperiodic reporting mode isconfigured, at least one of the bit width of the CRI, the bit width ofthe RI, the bit meaning of the CRI, or the bit meaning of the RI may bedetermined in a manner that is to be provided below by this embodimentof the present disclosure; in other words, at least one of the bit widthof the CRI, the bit width of the RI, the bit meaning of the CRI, or thebit meaning of the RI is related to the first indication information.Further, at least one of the bit width of the CRI, the bit width of theRI, the bit meaning of the CRI, or the bit meaning of the RI may befurther related to the reporting mode.

In the second possibility, the CSI measurement behavior may bedetermined without requiring a reporting mode configuration. Forexample, the reporting mode is specified in advance. If FeCoMPCSIEnabledis configured or the value of FeCoMPCSIEnabled is TRUE, it is limitedthat only the aperiodic reporting mode can be configured. In this case,whether FeCoMP-based measurement and reporting are used may bedetermined depending on whether FeCoMPCSIEnabled is configured orwhether the value of FeCoMPCSIEnabled is TRUE. That is, ifFeCoMPCSIEnabled is configured or the value of FeCoMPCSIEnabled is TRUE,it is determined to use FeCoMP-based measurement and/or feedback. If theFeCoMPCSIEnabled is not configured or the value of FeCoMPCSIEnabled isFALSE, it is determined to perform measurement and/or feedback in amanner in the prior art.

In this possibility, when FeCoMPCSIEnabled is configured or the value ofFeCoMPCSIEnabled is TRUE, at least one of the bit width of the CRI, thebit width of the RI, the bit meaning of the CRI, or the bit meaning ofthe RI may be determined in a manner that is to be provided below bythis embodiment of the present disclosure; in other words, at least oneof the bit width of the CRI, the bit width of the RI, the bit meaning ofthe CRI, or the bit meaning of the RI is related to the first indicationinformation.

In this embodiment of the present disclosure, the terminal device maydetermine at least one of the bit width of the CRI or the bit width ofthe RI based on the first indication information and at least one of aquantity of NZP CSI-RS resources, a quantity of antenna ports for an NZPCSI-RS, capability information of the terminal device, or a value of theCRI. That is, the bit width of the CRI and/or the bit width of the RIare/is related to the first indication information and at least one ofthe quantity of NZP CSI-RS resources, the quantity of antenna ports foran NZP CSI-RS, the capability information of the terminal device, or thevalue of the CRI. Alternatively, the terminal device may determine thebit meaning of the CRI and/or the bit meaning of the RI based on thefirst indication information and at least one of a quantity of NZPCSI-RS resources, a quantity of antenna ports for an NZP CSI-RS,capability information of the terminal device, the bit width of the RI,or a value of the CRI. That is, the bit meaning of the CRI and/or thebit meaning of the RI are/is related to the first indication informationand at least one of the quantity of NZP CSI-RS resources, the quantityof antenna ports for an NZP CSI-RS, the capability information of theterminal device, the bit width of the RI, or the value of the CRI.

In this embodiment of the present disclosure, the bit meaning may be aninformation feature included in a bit.

For example, the bit meaning of the RI may be reporting of a single RI,reporting of an RI in coordination (which is also referred to as an RIcombination (RI Combination)), or reporting of a plurality of RIs. Inaddition, the bit meaning of the RI may also be a mapping from a valueof the RI to a bit of the RI.

For example, the bit meaning of the RI may be a quantity of RIs that areto be fed back, for example, one RI, two RIs, or a plurality of RIS areto be fed back.

In one embodiment, a bit meaning of reporting of a single RI may be thatthe RI=1, 2, 3, . . . , or the like. For example, that the RI=1 meansthat the value of the RI is 1, and other cases are similar to this.

In one embodiment, a bit meaning of reporting of an RI combination meansthat an RI combination {RI 1, RI 2}={1, 1}, {1, 2}, {2, 1}, {2, 2}, . .. , or the like. For example, that {RI 1, RI 2}={1, 1} means that twoRIs are to be reported, and values of the two RIs are both 1.

In one embodiment, a bit meaning of reporting of a plurality of RIsmeans that an RI 1=1, 2, 3, . . . , or the like; an RI 2=1, 2, 3, . . ., or the like; and so on.

The following describes determining of the CSI feedback relatedinformation based on the first indication information. There are threecases:

Case 1: For coordinated multipoint transmission/reception mode (orFeCoMP or hybrid transmission mode)-based CSI feedback, the CRI and theRI are jointly encoded.

Case 2: For coordinated multipoint transmission/reception mode (orFeCoMP or hybrid transmission mode)-based CSI feedback, the CRI and theRI are separately encoded.

Case 3: For coordinated multipoint transmission/reception mode (orFeCoMP or hybrid transmission mode)-based CSI feedback, if CSI includesat least two RIs, the CRI and at least one of the RIs included in theCSI are jointly encoded. A remaining RI included in the CSI may not bejointly encoded with the CRI.

How to determine the coding scheme for the CRI and the RI is describedbelow. This embodiment may be an independent embodiment, or may becombined with another embodiment. This is not specifically limitedherein.

In this embodiment of the present disclosure, the CSI feedback relatedinformation may include at least one of the following: the CRI and theRI are jointly encoded; the CRI and the RI are separately encoded; orthe CRI includes at least two RIs, the CRI and at least one RI in the atleast two RIs are jointly encoded. In one embodiment, in this manner, aremaining RI in the at least one RI is not jointly encoded with the CRI.For example, when there are two RIs, the CRI and one of the RIs may bejointly encoded, and the other RI is not jointly encoded with the CRI.

In this case, the terminal device may determine the coding scheme forthe CRI and the RI based on the first indication information. Forexample, the determined coding scheme for the CRI and the RI is that:the CRI includes at least two RIs, and the CRI and at least one RI inthe at least two RIs are jointly encoded; or the determined codingscheme for the CRI and the RI is that: the CRI and the RI are separatelyencoded. Specifically, whether “the CRI and at least one RI in the atleast two RIs are jointly encoded” or the “CRI and the RI are separatelyencoded” may be determined based on a condition used in a protocol. Forexample, the coding scheme determined based on the first indicationinformation is determined from two selections in which the CRI and oneof the at least two RIs are jointly encoded and a remaining RI is notjointly encoded with the CRI, and the CRI and the RI are jointlyencoded. That is, if the terminal receives the first indicationinformation, the terminal determines, based on the first indicationinformation, that the coding scheme is that the CRI and one of the atleast two RIs are jointly encoded, and the remaining RI is not jointlyencoded with the CRI. If the terminal does not receive the firstindication information or receives other indication information, theterminal determines that the coding scheme is that the CRI and the RIare jointly encoded. Alternatively, the coding scheme determined basedon the first indication information is determined from separate encodingof the CRI and the RI and joint encoding of the CRI and the RI. That is,when the terminal receives the first indication information, theterminal determines, based on the first indication information, that thecoding scheme is that the CRI and the RI are separately encoded. If theterminal does not receive the first indication information or receivesother indication information, the terminal determines that the codingscheme is that the CRI and the RI are jointly encoded. The foregoingcoding scheme is merely an example, and another coding scheme is alsofeasible. This is not specifically limited herein.

In this embodiment of the present disclosure, joint encoding may also bejoint feedback. In this embodiment of the present disclosure,independent encoding (which refers to independent encoding with X and isalso referred to as non-joint encoding with X (or joint encoding withoutX) or separate encoding with X, for example, absolute independentencoding, which means that joint encoding is not performed with anyother information, where X is other information or a set of otherinformation) may be independent coding in joint feedback or may beindependent feedback (which refers to independent feedback with Y and isalso referred to as non-joint feedback with Y or separate feedback withY, for example, absolute independent feedback, which means that jointfeedback is not performed with any other information, where Y is otherinformation or a set of other information).

Joint feedback may be feedback in a same time unit, or may be feedbackon a same channel resource in a same time unit. Joint encoding may bechannel coding performed after bit concatenation.

Independent feedback may be feedback in different time units, or may befeedback on different channel resources in a same time unit. Independentencoding may be independent channel coding.

In one embodiment, in this embodiment of the present disclosure,independent RI feedback and/or independent RI encoding may also bereferred to as independent RI and CRI feedback and/or encoding, or maybe non-joint feedback and/or non-joint encoding with the CRI, or may beseparate feedback and/or separate encoding with the CRI. However, it isnot limited that joint feedback and/or joint encoding may be performedwith other CSI feedback information. For example, independent RIfeedback and/or independent feedback may mean that the RI and the CRIare independently encoded and/or independently fed back, and the RI isnot jointly fed back and/or jointly encoded with any CSI, or may meanthat the RI and the CRI are independently encoded and/or independentlyfed back, and the RI and at least one piece of CSI such as a PMI,precoding type indicator (PTI), or a CQI may be further jointly fed backand/or joint encoded. This is not specifically limited herein.

Five implementations of determining the bit width of the CRI and/or thebit width of the RI are described below. The first implementation(Method 1) and the second implementation (Method 2) may be solutionsspecific to the foregoing Case 1, and the third implementation (Method3) and the fourth implementation (Method 4) may be solutions specific tothe foregoing Case 2. The fifth implementation (Method 5) may be asolution specific to the foregoing Case 3. Further, a method fordetermining the bit meaning of the CRI and/or the bit meaning of the RIis further described.

Various implementations or methods in this embodiment of the presentdisclosure may be independent embodiments, or may be combined withanother embodiment. This is not specifically limited herein.

In one embodiment, in this embodiment of the present disclosure, asolution of determining based on the first indication information may bereplaced with a solution of determining based on the CSI measurementbehavior. For example, when the CSI measurement behavior can bedetermined without an indication by the first indication information, inthis embodiment of the present disclosure, the solution of determiningbased on the first indication information may be replaced with thesolution of determining based on the CSI measurement behavior. Thesolution of determining based on the CSI measurement action is notdescribed in detail herein.

For example, in this embodiment of the present disclosure, thedescription “when the first indication information is set toFeCoMPCSIEnabled or the value of FeCoMPCSIEnabled is TRUE” may also bereplaced with “when the CSI measurement behavior is FeCoMP-based CSImeasurement and/or feedback, or coordinated multipointtransmission/reception-based CSI measurement and/or feedback, or hybridtransmission mode-based CSI measurement and/or feedback”. That is, “whenthe first indication information is set to FeCoMPCSIEnabled or the valueof FeCoMPCSIEnabled is TRUE,” is replaced with “when the CSI measurementbehavior is FeCoMP-based CSI measurement and/or feedback, or coordinatedmultipoint transmission/reception-based CSI measurement and/or feedback,or hybrid transmission mode-based CSI measurement and/or feedback” isalso applicable to this embodiment of the present disclosure. Detailsare not described.

In one embodiment, in this embodiment of the present disclosure,“FeCoMPCSIEnabled is configured”, “the value of FeCoMPCSIEnabled isTRUE”, and “FeCoMPCSIEnabled and cqi-ReportModeAperiodic are configured”may represent a same condition, and may be replaced with each other.

In this embodiment of the present disclosure, the coordinated multipointtransmission/reception-based CSI measurement and/or feedback are/is alsoapplicable to FeCoMP-based CSI measurement and/or feedback, or alsoapplicable to hybrid transmission mode-based CSI measurement and/orfeedback, or also applicable to non-coherent transmission-based CSImeasurement and/or feedback. This is not specifically limited herein.

First implementation (namely, Method 1): The bit width of the CRI and/orthe bit width of the RI are/is determined based on the first indicationinformation.

In an example, in the first implementation, the bit width of the CRIand/or the bit width of the RI may be determined based on the firstindication information.

The bit width of the RI may be determined based on the first indicationinformation.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width usedwhen a single RI is reported and/or determining a total quantity of bitsoccupied by a plurality of RIs (or an RI combination) when the pluralityof RIs (or the RI combination) are reported. This is not specificallylimited herein.

Specifically, for example, when the first indication informationinstructs to enable FeCoMP-based CSI feedback, the bit width of the RIis fixed (for example, specified in a protocol), a CRI=0, a CRI=1, aCRI=2, and the like are not distinguished, and a quantity of antennaports and/or a capability of the terminal device are/is notdistinguished either.

The capability of the terminal device may be at least one of a maximumlayer quantity supported by the terminal (short for the terminaldevice), a maximum antenna port quantity supported by the terminal, amaximum transmission rate supported by the terminal, a transmission mode(for example, an open-loop mode, a closed-loop mode, a single-cell mode,or a coordinated mode) supported by the terminal, or the like.

For example, for an example in which two NZP CSI-RS resources areconfigured, when the first indication information instructs to enableFeCoMP-based CSI feedback, the bit width of the RI may be fixed to 4.Certainly, another value is also feasible. This is not limited herein.

In this embodiment of the present disclosure, when a base station (thenetwork device is described by using the base station as an example)determines to enable FeCoMP-based CSI feedback, the base station sendsthe first indication information, and determines that the bit width ofthe RI of the terminal is 4, to be specific, the bit width of the RI isrelated to the first indication information. When receiving the firstindication information, the terminal may determine the bit width of theRI based on the first indication information. For example, the bit widthof the RI is 4.

When determining not to enable FeCoMP-based CSI feedback, the basestation does not send the first indication information, and determinesthe bit width of the RI based on the prior art. When not receiving thefirst indication information, the terminal may determine the bit widthof the RI based on the prior art. The determining the bit width of theRI in the prior art is that, for example, the bit width of the RI isrelated to the quantity of antenna ports and the capability of theterminal device. Specifically, for example, if the quantity of antennaports is 4, and the capability of the terminal device may supporttransmission of a maximum of four layers, the bit width of the RI is 2.

For descriptions of implementations of the terminal and the basestation, refer to other parts in this embodiment. An implementation ofthe terminal is as an example for description below.

How to determine the bit width of the CRI and/or the bit meaning of theCRI is described below. Determining of the bit width of the CRI and/orthe bit meaning of the CRI may be an independent embodiment, or may becombined with another embodiment. This is not specifically limitedherein.

Determining method A: The bit width of the CRI and/or the bit meaning ofthe CRI are/is determined based on the first indication information.

Specifically, the terminal determines the bit width of the CRI based onthe first indication information, and/or the terminal determines the bitmeaning of the CRI based on the first indication information.

For example, when the terminal receives the first indicationinformation, and FeCoMP-based CSI feedback is enabled, for example, whenthe first indication information is set to FeCoMPCSIEnabled or the valueof FeCoMPCSIEnabled is TRUE, the terminal may determine the bit width ofthe CRI, for example, the bit width of the CRI is 2. When determining toenable FeCoMP-based CSI feedback for the terminal, the base stationsends the first indication information, and determines that the bitwidth of the CRI of the terminal is 2. Herein, the bit width of the CRIthat is 2 is merely an example, and another value is also feasible. Thisis not specifically limited.

For example, when the terminal receives the first indicationinformation, and FeCoMP-based CSI feedback is enabled, for example, whenthe first indication information is set to FeCoMPCSIEnabled or the valueof FeCoMPCSIEnabled is TRUE, the terminal may determine the bit meaningof the CRI. For example, the bit meaning when the bit width of the CRIis 2 is specifically as follows: For example, 00 represents that theCRI=0, indicating that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource; 01 represents that the CRI=1,indicating that reported CSI is obtained through measurement based onthe second NZP CSI-RS resource; and 11 represents that reported CSI isobtained through measurement based on the first NZP CSI-RS resource andthe second NZP CSI-RS resource. When determining to enable FeCoMP-basedCSI feedback, the base station sends the first indication information,and determines that the bit width of the CRI of the terminal is 2 and/ordetermines the bit meaning of the CRI. Herein, the bit width of the CRIthat is 2 is merely an example, and another value is also feasible. Thisis not specifically limited.

In one embodiment, when the terminal does not receive the firstindication information, for example, when the first indicationinformation is not set to FeCoMPCSIEnabled or the value ofFeCoMPCSIEnabled is FALSE, the bit width of the CRI may be determinedbased on the prior art, for example, determined based on a quantity K ofconfigured NZP CSI-RS resources. For example, the bit width of the CRIis ┌log₂(K)┐. K is a positive integer, and ┌ ┐ represents rounding up.

Determining method B: The bit width of the CRI and/or the bit meaning ofthe CRI are/is determined based on the first indication information andat least one of the quantity of NZP CSI-RS resources, the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the value of the CRI.

In an example, the bit width of the CRI and/or the bit meaning of theCRI may be determined based on the first indication information and thequantity K of configured NZP CSI-RS resources.

Specifically, when the first indication information is set toFeCoMPCSIEnabled or the value of FeCoMPCSIEnabled is TRUE, the bit widthof the CRI is determined based on the quantity of configured NZP CSI-RSresources. For example, if the quantity of configured NZP CSI-RSresources is 2, the bit width of the CRI is 2. When the first indicationinformation is not set to FeCoMPCSIEnabled or the value ofFeCoMPCSIEnabled is FALSE, the bit width of the CRI is determined basedon the quantity K of configured NZP CSI-RS resources. For example, thebit width of the CRI is ┌log₂(K)┐. For example, if the quantity K ofconfigured NZP CSI-RS resources is 2, the bit width of the CRI is 1.

In this embodiment of the present disclosure, a relationship between thequantity of configured NZP CSI-RS resources and the bit width of the CRIand/or the bit meaning of the CRI may include at least one of thefollowing:

-   -   1. In coordinated multipoint transmission/reception (or FeCoMP        or hybrid transmission mode or non-coherent transmission        mode)-based CSI measurement and/or feedback, when the quantity        of NZP CSI-RS resources is K, the bit width of the CRI may be        ┌log₂ (K+C_(K) ²┐.

For example, four NZP CSI-RS resources are configured, and incoordinated multipoint transmission/reception (or FeCoMP or hybridtransmission mode or non-coherent transmission mode)-based CSImeasurement and/or feedback, four cases may be included in a single-cellscenario. In a coordinated multipoint transmission/reception scenario orFeCoMP, any two resources are selected from the four NZP CSI-RSresources. To be specific, there may be C_(K) ² cases. Therefore, theCRI needs to indicate a total of K+C_(K) ² cases. That is, the bit widthof the CRI may be ┌log₂ (K+C_(K) ²)┐. K is the quantity of NZP CSI-RSresources.

For example, K=4. In this case, a total of 4 bits are needed to indicatethe value of the CRI. In this case, the bit meaning of the CRI may be atleast one of the following, and a decimal system is used below torepresent the value of the CRI. It may be understood that the value ofthe CRI may also be represented by using a binary, octal, or hexadecimalsystem. The value in this embodiment of the present disclosure isrepresented by using one number system, but is not limited to theenumerated number system:

The CRI=0 indicates that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource.

The CRI=1 indicates that reported CSI is obtained through measurementbased on the second NZP CSI-RS resource.

The CRI=2 indicates that reported CSI is obtained through measurementbased on the third NZP CSI-RS resource.

The CRI=3 indicates that reported CSI is obtained through measurementbased on the fourth NZP CSI-RS resource.

The CRI=4 indicates that reported CSI is obtained through measurementbased on the first and second NZP CSI-RS resources.

The CRI=5 indicates that reported CSI is obtained through measurementbased on the first and third NZP CSI-RS resources.

The CRI=6 indicates that reported CSI is obtained through measurementbased on the first and fourth NZP CSI-RS resources.

The CRI=7 indicates that reported CSI is obtained through measurementbased on the second and third NZP CSI-RS resources.

The CRI=8 indicates that reported CSI is obtained through measurementbased on the second and fourth NZP CSI-RS resources.

The CRI=9 indicates that reported CSI is obtained through measurementbased on the third and fourth NZP CSI-RS resources.

4 bits may be used to indicate the value of the CRI, and specific bitmapping may be any item in the following table.

TABLE X21 O₀ ^(RI), O₁ ^(RI), O₂ ^(RI), O₃ ^(RI) to CRI mapping O₀^(RI), O₁ ^(RI), O₂ ^(RI), O₃ ^(RI) CRI 0, 0, 0, 0 0 0, 0, 0, 1 1 0, 0,1, 0 2 0, 0, 1, 1 3 0, 1, 0, 0 4 0, 1, 0, 1 5 0, 1, 1, 0 6 0, 1, 1, 1 71, 0, 0, 0 8 1, 0, 0, 1 9 1, 0, 1, 0 Reserved 1, 0, 1, 1 Reserved 1, 1,0, 0 Reserved 1, 1, 0, 1 Reserved 1, 1, 1, 0 Reserved 1, 1, 1, 1Reserved

The value of the bit width of the CRI herein is merely an example, thebit meaning of the CRI is also merely an example, and a correspondencebetween a bit value and the value of the CRI in the table is also merelyan example. Another value or correspondence is not limited.

In the foregoing embodiment, the value or the bit meaning of the CRIindicates a meaning of CSI feedback. In one embodiment, the meaning ofCSI feedback may be indicated by using another piece of information, forexample, first feedback information. In other words, the first feedbackinformation is used to indicate the meaning of CSI feedback. The meaningof CSI feedback may be at least one of a CSI measurement result incoordinated multipoint transmission/reception, a measurement result insingle-cell transmission, or a CSI measurement result in FeCoMP.Alternatively, the meaning of CSI feedback may be at least one of firstCSI, second CSI, third CSI, or fourth CSI. The first CSI is obtainedbased on interference power; the second CSI is obtained based oninterference that is obtained by using a preset algorithm when aresource used for channel measurement is the same as a resource used forinterference measurement; the third CSI is obtained based oninterference power and interference that is obtained by using a presetalgorithm when a resource used for channel measurement is the same as aresource used for interference measurement; and the fourth CSI isobtained based on inter-stream interference or inter-codewordinterference.

For example, the terminal may feed back the first feedback information.The first feedback information is used to indicate the meaning of CSIfeedback. According to the method, the base station may determine, byreceiving the first feedback information, a meaning of CSI feedback thatcorresponds to received CSI. The implementation may be an independentembodiment, or may be combined with another embodiment. This is notspecifically limited herein.

In this embodiment of the present disclosure, when the terminal receivesthe first indication information, where the first indication informationinstructs to enable coordinated multipoint transmission/reception (orFeCoMP or hybrid transmission mode or non-coherent transmissionmode)-based CSI measurement and/or feedback, the terminal determines,based on the first indication information and the quantity of NZP CSI-RSresources, that the bit width of the CRI is ┌log₂(K+C_(K) ²)┐.Similarly, for a base station side, when determining to enableFeCoMP-based CSI feedback for the terminal, the base station sends thefirst indication information, and determines that the bit width of theCRI of the terminal is ┌log₂(K+C_(K) ²)┐. K is the quantity of NZPCSI-RS resources.

When the terminal does not receive the first indication information,that is, coordinated multipoint transmission/reception (or FeCoMP orhybrid transmission mode or non-coherent transmission mode)-based CSImeasurement and/or feedback are/is not enabled, for example, when normalmeasurement feedback or single-cell measurement and feedback areperformed, when the quantity of NZP CSI-RS resources is K, the bit widthof the CRI may be ┌log₂(K)┐. K is a positive integer, and

$C_{K}^{2} = {\frac{K \times \left( {K - 1} \right)}{2}.}$

-   -   2. In coordinated multipoint transmission/reception (or FeCoMP        or hybrid transmission mode or non-coherent transmission        mode)-based CSI measurement and feedback, when the quantity of        NZP CSI-RS resources is K, the bit width of the CRI may be        ┌log₂(K+C_(K-1) ¹)┐ or another specified bit width, or is        calculated based on another specified calculation formula. This        is not specifically limited herein.

For example, K=4. In this case, a total of 3 bits are needed to indicatethe value of the CRI. In this case, the bit meaning of the CRI may be atleast one of the following, and a decimal system is used below torepresent the value of the CRI. It may be understood that the value ofthe CRI may also be represented by using a binary, octal, or hexadecimalsystem. The value in this embodiment of the present disclosure isrepresented by using one number system, but is not limited to theenumerated number system:

The CRI=0 indicates that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource.

The CRI=1 indicates that reported CSI is obtained through measurementbased on the second NZP CSI-RS resource.

The CRI=2 indicates that reported CSI is obtained through measurementbased on the third NZP CSI-RS resource.

The CRI=3 indicates that reported CSI is obtained through measurementbased on the fourth NZP CSI-RS resource.

The CRI=4 indicates that reported CSI is obtained through measurementbased on the first and second NZP CSI-RS resources.

The CRI=5 indicates that reported CSI is obtained through measurementbased on the first and third NZP CSI-RS resources.

The CRI=6 indicates that reported CSI is obtained through measurementbased on the first and fourth NZP CSI-RS resources.

3 bits may be used to indicate the value of the CRI, and specific bitmapping may be any item in the following table.

TABLE X21 O₀ ^(RI), O₁ ^(RI), O₂ ^(RI) to CRI mapping O₀ ^(RI), O₁^(RI), O₂ ^(RI) CRI 0, 0, 0 0 0, 0, 1 1 0, 1, 0 2 0, 1, 1 3 1, 0, 0 4 1,0, 1 5 1, 1, 0 6 1, 1, 1 Reserved

The value of the bit width of the CRI herein is merely an example, thebit meaning of the CRI is also merely an example, and a correspondencebetween a bit value and the value of the CRI in the table is also merelyan example. Another value or correspondence is not limited.

During normal measurement such as single-cell measurement and feedback,when the quantity of NZP CSI-RS resources is K, the bit width of the CRImay be ┌log₂(K)┐.

An example in which two NZP CSI-RS resources are configured is usedbelow to describe determining the bit width of the CRI and/or the bitwidth of the RI based on a quantity of NZP CSI-RS resources and thefirst indication information.

Specifically, when two NZP CSI-RS resources are configured, and thefirst indication information indicates that CSI measurement and feedbackare FeCoMP-based CSI feedback, it may be determined that the bit widthof the RI is 4, and the bit width of the CRI is 2.

The value herein is merely an example, and another value is alsofeasible. This is not specifically limited.

Specifically, the terminal may determine, by using the method in theforegoing embodiment, that the CSI measurement behavior is FeCoMP-basedCSI measurement. For example, the first indication information isconfigured, and the first indication information is used to enableFeCoMP-based CSI feedback, or enable coordinated multipointtransmission/reception-based CSI feedback, or enable hybrid transmissionmode-based CSI feedback. For example, the first indication informationis the higher layer parameter FeCoMPCSIEnabled, and determining isperformed by configuring the higher layer parameter FeCoMPCSIEnabled orconfiguring FeCoMPCSIEnabled=TRUE (to be specific, determining isperformed based on the first indication information). The followingembodiment is specifically described by using a solution in which thehigher layer parameter FeCoMPCSIEnabled is configured. A solution inwhich FeCoMPCSIEnabled=TRUE is configured is similar to this, anddetails are not described herein.

In one embodiment, for at least one of the three existing reportingmodes, namely, at least one of wideband CQI reporting (that is,reporting a wideband CQI), higher layer-configured subband CQI reporting(that is, reporting a higher layer-configured subband CQI), or UEselected subband CQI reporting (that is, reporting a terminal selectedsubband CQI), respective bit quantities for CRI and/or RI feedback maybe defined, or a bit width for CRI and/or RI feedback may be uniformlydescribed. A unified description and a separate description may meanthat the terminal and/or the base station may store a mappingrelationship such as a mapping table, a mapping sequence, or a mappingformula for different reporting modes, or may store respective mappingrelationships such as mapping tables, mapping sequences, or mappingformulas.

Specifically, the reporting mode in this embodiment of the presentdisclosure may alternatively be a reporting mode in NR (New Radio, newradio communications technology), 5G, or a future research system. Thisis not specifically limited herein.

In this embodiment of the present disclosure, a transmission mode 10 isused as an example in the table. That is, FeCoMP-based CSI measurementand/or feedback can be applied only to a terminal in the transmissionmode 10 in an LTE system, but is not applicable to another transmissionmode in the LTE system. In this embodiment of the present disclosure,FeCoMP-based CSI measurement and/or feedback are/is also applicable to atransmission mode in NR, 5G, or a future communications system, and isnot limited to the transmission mode 10. In this case, the transmissionmode 10 is merely an example, and another transmission mode is notlimited herein. Alternatively, FeCoMP-based CSI measurement and/orfeedback are/is also applicable to any transmission mode, that is,FeCoMP-based CSI measurement and/or feedback are/is unrelated to atransmission mode.

For example, for at least one of the three reporting modes, for aunified description manner, refer to at least one item in Table5.2.2.6.3-3F:

When the terminal configures the transmission mode 10 and the higherlayer parameter FeCoMPCSIEnabled, a bit width for joint CRI and RIfeedback is shown in Table 5.2.2.6.3-3F. The terminal and/or the basestation may store only one mapping table, mapping sequence, or mappingformula.

TABLE 5.2.2.6.3-3F Scenarios for joint CRI and RI feedback (Fields forjoint CRI and RI feedback) (the transmission mode 10 and the higherlayer parameter FeCoMPCSIEnabled) Scenario/field Bit width CRI 2 Rankindication 4

It can be learned from Table 5.2.2.6.3-3F that, when the terminalconfigures the higher layer parameter FeCoMPCSIEnabled, for at least oneof the three reporting modes, the bit width of the CRI is 2, and the bitwidth of the RI is 4.

For example, for at least one of the three reporting modes, a separatedescription manner may be at least one of the following:

The terminal maintains mapping relationships such as mapping tables,mapping sequences, or mapping formulas corresponding to differenttransmission modes based on the reporting mode, for example, for atleast one of the three reporting modes.

A. When the terminal configures FeCoMPCSIEnabled (or configuresFeCoMPCSIEnabled and the aperiodic reporting mode), for wideband CQIreporting, a bit width for CRI and RI (or RI combination) feedback isfixed, and refer to Table 5.2.2.6.1-2F: For example, for wideband CQIreporting, the terminal may store Table 5.2.2.6.1-2F, that is, whenwideband CQI reporting and the first indication information areconfigured, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.1-2F.

TABLE 5.2.2.6.1-2F Scenarios for joint CRI and RI feedback for widebandCQI reporting (Fields for joint CRI and RI feedback for wideband CQIreports) (the transmission mode 10 and the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2 Rank indication 4

B. When the terminal configures FeCoMPCSIEnabled (or configuresFeCoMPCSIEnabled and the aperiodic reporting mode), for higherlayer-configured subband CQI reporting, a bit width for CRI and RI (orRI combination) feedback is fixed, and refer to Table 5.2.2.6.2-3F1: Forexample, for higher layer-configured subband CQI reporting, the terminalmay store Table 5.2.2.6.2-3F1, that is, when higher layer-configuredsubband CQI reporting and the first indication information areconfigured, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.2-3F1.

TABLE 5.2.2.6.2-3F1 Scenarios for joint CRI and RI feedback for higherlayer-configured subband CQI reporting (Fields for joint CRI and RIfeedback for higher layer configured subband CQI reports) (thetransmission mode 10 and the higher layer parameter FeCoMPCSIEnabled)Field Bit width CRI 2 Rank indication 4

C. When the terminal configures FeCoMPCSIEnabled (or configuresFeCoMPCSIEnabled and the aperiodic reporting mode), for UE selectedsubband CQI reporting, a bit width for CRI and RI (or RI combination)feedback is fixed, and specifically refer to Table 5.2.2.6.3-3F2: Forexample, for UE selected subband CQI reporting, the terminal may storeTable 5.2.2.6.3-3F2, that is, when UE selected subband CQI reporting andthe first indication information are configured, the terminal may usebit quantities of the CRI and the RI in Table 5.2.2.6.3-3F2.

TABLE 5.2.2.6.3-3F2 Scenarios for joint CRI and RI feedback for UEselected subband CQI reporting (Fields for joint CRI and RI feedback forUE selected subband CQI reports) (the transmission mode 10 and thehigher layer parameter FeCoMPCSIEnabled) Field Bit width CRI 2 Rankindication 4

Through the first implementation described above, when the RI and theCRI are jointly fed back and/or jointly encoded, the bit width of the RIis enabled to be independent of the value of the CRI, to be specific, itcan be ensured that the bit width of the CRI and the bit width of the RIare fixed, so that the base station can correctly receive and/or decodethe CRI and the RI. Certainly, because the bit width of the RI is fixed,overheads for the bit width of the RI may be relatively high.

Second implementation (namely, Method 2): The bit width of the CRIand/or the bit width of the RI are/is determined based on the firstindication information and at least one of the quantity of NZP CSI-RSresources, the quantity of antenna ports for an NZP CSI-RS, thecapability information of the terminal device, or the value of the CRI.In an example, the bit width of the RI may be determined based on thefirst indication information and the quantity of antenna ports and/orthe capability information of the terminal device. In the secondimplementation, the bit width of the RI is determined based on the firstindication information and the quantity of antenna ports and/or thecapability information of the terminal device, without considering thevalue of the CRI. For example, the CRI=0, the CRI=1, and the CRI=2 arenot distinguished.

In one embodiment, in Method 1 to Method 4 in this embodiment of thepresent disclosure, the determining the bit width of the RI may bedetermining a bit width of an RI used when a single RI is reportedand/or determining a total quantity of bits occupied by a plurality ofRIs (or an RI combination) when the plurality of RIs (or the RIcombination) are reported. This is not specifically limited herein.

An example in which more than one NZP CSI-RS resource is configured isused to describe determining the bit width of the RI based on the firstindication information and the quantity of antenna ports and/or thecapability information of the terminal device.

Method 2.1: The bit width of the RI is determined based on the firstindication information and whether the quantity of antenna ports is 1.

In the following description process, when the quantity of antenna portsis used, only two cases in which the quantity of antenna ports is 1 andthe quantity of antenna ports is greater than 1 are distinguished.

In the present disclosure, when more than one NZP CSI-RS resource isconfigured, if there is no special description about an NZP CSI-RSresource to which the quantity of antenna ports corresponds, thequantity of antenna ports may be a maximum value of quantities ofantenna ports corresponding to the more than one configured NZP CSI-RSresource.

For example, if the quantity of antenna ports is 1, it indicates thatthe maximum value of the quantities of antenna ports corresponding tothe more than one configured NZP CSI-RS resource is 1, that is, aquantity of antenna ports corresponding to each NZP CSI-RS resourceis 1. If the quantity of antenna ports is greater than 1, it indicatesthat the maximum value of the quantities of antenna ports correspondingto the more than one configured NZP CSI-RS resource is greater than 1,that is, a quantity of antenna ports for at least one NZP CSI-RSresource is greater than 1.

Specifically, when the quantity of antenna ports is 1, the RI is not fedback. When the quantity of antenna ports is greater than 1, a value ofthe bit width of the RI is specified, for example, 4.

That is, in this embodiment of the present disclosure, the terminal maydetermine, based on the first indication information and the quantity ofantenna ports that is 1, not to feed back the RI, and feed back only theCRI. The terminal may determine, based on the first indicationinformation and the quantity of antenna ports that is greater than 1,the bit width of the RI, for example, 4. The value of 4 of the bit widthis merely an example, and another value is also feasible. This is notspecifically limited herein.

Examples are as follows:

In one embodiment, for at least one of the three existing reportingmodes (wideband CQI reporting, higher layer-configured subband CQIreporting, and UE selected subband CQI reporting), bit quantities forCRI and/or RI feedback may be respectively defined, or a bit width forCRI and/or RI feedback may be uniformly described. A unified descriptionand a separate description may mean that the terminal device and/or thebase station may store one or more mapping tables, mapping sequences, ormapping formulas for different reporting modes, or may store respectivemapping tables, mapping sequences, or mapping formulas.

Specifically, the reporting mode in this embodiment of the presentdisclosure may alternatively be a reporting mode in NR, 5G, or a futureresearch system. This is not specifically limited herein.

In one embodiment, the table in this embodiment of the presentdisclosure is an example in which the terminal and/the base stationare/is applicable to enabling of FeCoMP-based CSI measurement and/orfeedback only in a condition in which a CSI-RS resource of a class B isconfigured. That is, the first indication information is configured onlywhen a higher layer parameter eMIMO-Type is set to a class B and K>1 NZPCS-RS resources are configured. Alternatively, further, the firstindication information is configured only when a higher layer parametereMIMO-Type is set to a class B and two NZP CS-RS resources areconfigured. This condition is merely an example, and an applicablecondition for enabling FeCoMP-based CSI measurement and/or feedback mayalso be another condition, for example, a condition in which a CSI-RSresource of a class A is configured is also applicable. This is notspecifically limited herein. The NZP CSI-RS resource of the class B maybe an NZP CSI-RS resource on which precoding or beamforming isperformed, that is, a precoding or beamforming operation is performed ona CSI-RS before the CSI-RS is sent. The NZP CSI-RS resource of the classA may be an NZP CSI-RS resource on which precoding or beamforming is notperformed, that is, no precoding or beamforming operation is performedon a CSI-RS before the CSI-RS is sent.

In one embodiment, when the table in this embodiment of the presentdisclosure is described, only the transmission mode 10 and configurationof a PMI/RI feedback condition are used as an example to describe thebit width of the CRI and/or the bit width of the RI. This condition ismerely an example, and may also be another condition, for example, noPMI feedback is configured. This is not specifically limited herein.

For example, for a unified description manner, refer to at least oneitem in Table 5.2.2.6.1-2F1 and Table 5.2.2.6.1-2G1. Table 5.2.2.6.1-2F1shows a case in which the quantity of antenna ports is greater than 1,and Table 5.2.2.6.1-2G1 shows a case in which the quantity of antennaports is 1:

For example, for the configured first indication information and thequantity of antenna ports that is greater than 1, the terminal maydetermine the bit quantities of the CRI and the RI by using at least oneitem in Table 5.2.2.6.1-2F1. For the configured first indicationinformation and the quantity of antenna ports that is 1, the terminalmay determine the bit quantities of the CRI and the RI by using at leastone item in Table 5.2.2.6.1-2G1.

TABLE 5.2.2.6.1-2F1 Scenarios for joint CRI and RI feedback (Fields forjoint CRI and RI feedback) (the transmission mode 10 is configured withPMI/RI reporting and the higher layer parameter enhanced multiple- inputmultiple-output (eMIMO)-type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and more than one antenna portfor at least one CSI-RS resource and the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2 Rank indication 4

TABLE 5.2.2.6.1-2G1 Scenarios for the CRI (Fields for CRI) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CRI-RS resources and one antenna port for eachCRI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

In the scenario of Table 5.2.2.6.1-2G1, the RI is not fed back, andtherefore, it may be considered that the bit width of the RI is 0.

The unified description manner is described above. For example, for atleast one of the three reporting modes, a separate description mannermay be at least one of the following:

A. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for wideband CQI reporting, abit width for CRI and RI (or RI combination) feedback is specifically asfollows:

For example, for wideband CQI reporting, the terminal may store at leastone item in two tables such as Table 5.2.2.6.1-2F2 and Table5.2.2.6.1-2G2. That is, when wideband CQI reporting is configured andthe first indication information is configured and the quantity ofantenna ports is greater than 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.1-2F2. When wideband CQI reportingis configured and the first indication information is configured and thequantity of antenna ports is 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.1-2G2.

TABLE 5.2.2.6.1-2F2 Scenarios for joint CRI and RI feedback for widebandCQI reporting (Fields for joint CRI and RI feedback for wideband CQIreports) (the transmission mode 10 is configured with PMI/RI reportingand the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ configured with K > 1 CSI-RS resources and more than oneantenna port for at least one CSI-RS resource and configured with thehigher layer parameter FeCoMPCSIEnabled) Field Bit width CRI 2 Rankindication 4

TABLE 5.2.2.6.1-2G2 Scenarios for CRI feedback for wideband CQIreporting (Fields for CRI feedback for wideband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and one antenna port for eachCSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

B. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for higher layer-configuredsubband CQI reporting, a bit width for CRI and RI (or RI combination)feedback is specifically as follows:

For example, for higher layer-configured subband CQI reporting, theterminal may store at least one item in Table 5.2.2.6.2-3F1 and Table5.2.2.6.2-3G1. That is, when higher layer configured subband CQIreporting is configured and the first indication information isconfigured and the quantity of antenna ports is greater than 1, theterminal may use bit quantities of the CRI and the RI in Table5.2.2.6.2-3F1. When higher layer-configured subband CQI reporting isconfigured and the first indication information is configured and thequantity of antenna ports is 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.2-3G1.

TABLE 5.2.2.6.2-3F1 Scenarios for joint CRI and RI feedback for higherlayer-configured subband CQI reporting (Fields for joint CRI and RIfeedback for higher layer configured subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and more than one antenna portfor at least one CSI-RS resource and configured with the higher layerparameter FeCoMPCSIEnabled) Field Bit width CRI 2 Rank indication 4

TABLE 5.2.2.6.2-3G1 Scenarios for CRI feedback for higherlayer-configured subband CQI reporting (Fields for CRI feedback forhigher layer configured subband CQI reports) (the transmission mode 10is configured with PMI/RI reporting and the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ configured with K > 1CSI-RS resources and one antenna port for each CSI-RS resource andconfigured with the higher layer parameter FeCoMPCSIEnabled) Field Bitwidth CRI 2

C. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for UE selected subband CQIreporting, a bit width for CRI and RI (or RI combination) feedback isspecifically as follows:

For example, for UE selected subband CQI reporting, the terminal maystore at least one item in Table 5.2.2.6.3-3F2 and Table 5.2.2.6.3-3G2.That is, when UE selected subband CQI reporting and the first indicationinformation are configured and the quantity of antenna ports is greaterthan 1, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.3-3F2. When UE selected subband CQI reporting isconfigured and the first indication information is configured and thequantity of antenna ports is 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.3-3G2.

TABLE 5.2.2.6.3-3F2 Scenarios for joint CRI and RI feedback for UEselected subband CQI reporting (Fields for joint CRI and RI feedback forUE selected subband CQI reports) (the transmission mode 10 is configuredwith PMI/RI reporting and the higher layer parameter eMIMO-Type, andeMIMO-Type is set to the ‘CLASS B’ configured with K > 1 CSI-RSresources and more than one antenna port for at least one CSI-RSresource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2 Rank indication 4

TABLE 5.2.2.6.3-3G2 Scenarios for CRI feedback for UE selected subbandCQI reporting (Fields for CRI feedback for UE selected subband CQIreports) (the transmission mode 10 is configured with PMI/RI reportingand the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ configured with K > 1 CSI-RS resources and one antenna portfor each CSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

Through the foregoing implementation, the bit width of the RI may bedetermined respectively for two cases: the quantity of antenna ports is1 and the quantity of antenna ports is greater than 1, so that bitoverheads of the RI can be reduced and performance can be improved.

The following embodiment is used to describe a method for determiningthe bit meaning of the RI. This embodiment of the present disclosure maybe an independent embodiment, or may be combined with anotherembodiment. This is not specifically limited herein.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width usedwhen a single RI is reported and/or determining a total quantity of bitsoccupied by a plurality of RIs (or an RI combination) when the pluralityof RIs (or the RI combination) are reported. This is not specificallylimited herein.

In one embodiment, for the second implementation, a more detailedsolution is further provided.

Method 2.2: The bit width of the RI is determined based on the firstindication information and at least one of the quantity of antenna portsfor an NZP CSI-RS resource and the capability information of theterminal device (which is referred to as the capability of the terminaldevice for short).

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width of anRI used when a single RI is reported and/or determining a total quantityof bits occupied by a plurality of RIs (or an RI combination) when theplurality of RIs (or the RI combination) are reported. This is notspecifically limited herein.

This embodiment may be independently implemented, or may be applied incombination with another embodiment. This is not specifically limitedherein.

Specifically, for example, when the quantity of antenna ports for an NZPCSI-RS resource is 1, the RI is not fed back. When the quantity ofantenna ports for an NZP CSI-RS resource is greater than 1, the bitwidth of the RI may be determined based on the first indicationinformation and at least one of the quantity of antenna ports and thecapability of the terminal device. For example, when the firstindication information is configured and the quantity of antenna portsis 2 and/or the capability of the terminal device is that a supportedmaximum layer quantity is 2, the bit width of the RI is 2, or when thefirst indication information is configured and the quantity of antennaports for an NZP CSI-RS resource is 4 and/or the capability of theterminal device is that a supported maximum layer quantity is 4, the bitwidth of the RI is 4.

In one embodiment, in this embodiment of the present disclosure, if aplurality of CSI-RS resources are configured, when the bit width of theRI is determined, the quantity of antenna ports for an NZP CSI-RSresource that is based on may be a maximum value of quantities ofantenna ports corresponding to the configured NZP CSI-RS resources. Forexample, two NZP CSI-RS resources are configured, a quantity of antennaports for one NZP CSI-RS resource is 2, and a quantity of antenna portsfor the other NZP CSI-RS resource is 4. In this case, the bit width ofthe RI is determined based on the quantity of antenna ports that is 4. Aquantity of antenna ports corresponding to a resource may be understoodas a quantity of antenna ports used to transmit the resource.

In one embodiment, for at least one of the three existing reportingmodes (wideband CQI reporting, higher layer-configured subband CQIreporting, and UE selected subband CQI reporting), bit quantities forCRI and/or RI feedback may be respectively defined, or a bit width forCRI and/or RI feedback may be uniformly described. A unified descriptionmay mean that the terminal and/or the base station may store one or moremapping tables, mapping sequences, or mapping formulas for differentreporting modes. A separate description may mean that the terminaland/or the base station may store mapping relationships such as mappingtables, mapping sequences, or mapping formulas corresponding todifferent reporting modes for the reporting modes.

Specifically, the reporting mode in this embodiment of the presentdisclosure may alternatively be a reporting mode in NR, 5G, or a futureresearch system. This is not specifically limited herein.

For example, a unified description manner may include at least one itemin Table 5.2.2.6.3-3F3 and Table 5.2.2.6.3-3G3. Table 5.2.2.6.3-3F3shows a case in which the quantity of antenna ports is greater than 1,and Table 5.2.2.6.1-2G1 shows a case in which the quantity of antennaports is 1:

For example, for the configured first indication information and thequantity of antenna ports that is greater than 1, the terminal stores atleast one item in Table 5.2.2.6.3-3F3. For the configured firstindication information and the quantity of antenna ports that is 1, theterminal stores at least one item in Table 5.2.2.6.3-3G3. The terminalmay store a total of two tables.

TABLE 5.2.2.6.3-3F3 Scenarios for joint CRI and RI/RI combinationfeedback (Fields for joint CRI and RI/RI Combination feedback) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and more than one antenna portfor at least one CSI-RS resource and configured with the higher layerparameter FeCoMPCSIEnabled) Bit width 4 antenna 8 antenna ports portsMax 1 Max 1 2 antenna or 2 Max 4 or 2 Max 4 Max 8 Field ports layerslayers layers layers layers CRI 2 2 2 2 2 2 Rank 2 2 4 2 4 4 indication

It can be learned from Table 5.2.2.6.3-3F3 that, for example, when thequantity of antenna ports is 2, the bit width of the CRI is 2, and thebit width of the RI is also 2. Alternatively, when the quantity ofantenna ports is 4 and the capability of the terminal device is that thesupported maximum layer quantity is 4, the bit width of the CRI is 2,and the bit width of the RI is 4.

TABLE 5.2.2.6.3-3G3 Scenarios for CRI feedback (Fields for CRI feedback)(the transmission mode 10 is configured with PMI/RI reporting and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ configured with K > 1 CSI-RS resources and one antenna port for eachCSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

Table 5.2.2.6.3-3G3 indicates a case in which the quantity of antennaports is 1, and the RI is not fed back. It may be considered that thebit width of the RI is 0.

The unified description manner of at least one of the three reportingmodes is described above, and a separate description manner may be atleast one of the following. Examples are as follows:

A. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for wideband CQI reporting, abit width for CRI and RI (or RI combination) feedback may include atleast one item in Table 5.2.2.6.3-3F4 and Table 5.2.2.6.3-3G4:

For example, for wideband CQI reporting, the terminal may store at leastone item in two tables such as Table 5.2.2.6.3-3F4 and Table5.2.2.6.3-3G4. That is, when wideband CQI reporting is configured andthe first indication information is configured and the quantity ofantenna ports is greater than 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.3-3F4. When wideband CQI reportingis configured and the first indication information is configured and thequantity of antenna ports is 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.3-3 G4.

TABLE 5.2.2.6.3-3F4 Fields for joint CRI and RI/RI Combination feedbackfor wideband CQI reports (transmission mode 10 configured with PMI/RIreporting and higher layer parameter eMIMO-Type, and eMIMO-Type is setto ‘CLASS B’ with K > 1 CSI-RS resources and more than one port for atleast one CSI-RS resource and higher layer parameter FeCoMPCSIEnabled)Bit width 4 antenna 8 antenna ports ports Max 1 Max 1 2 antenna or 2 Max4 or 2 Max 4 Max 8 Field ports layers layers layers layers layers CRI 22 2 2 2 2 Rank 2 2 4 2 4 4 indication

In Table 5.2.2.6.3-3F4, when the bit width of the RI is 2, anothercorrespondence may be obtained by replacing the bit width of the RI with3 or increasing the bit width of the RI to 3. For example, when thequantity of antenna ports is 2, the bit width of the CRI is 2, and thebit width of the RI may be 2 or 3. Similarly, when the quantity ofantenna ports is 4, the capability of the terminal device is that thesupported maximum layer quantity is 1 or 2, and the RI bit width may be2, 3, or the like. Specifically, whether a value is 2 or 3 may bepredefined in a protocol, or notified by the base station to theterminal. This is not specifically limited herein.

TABLE 5.2.2.6.3-3G4 Scenarios for CRI feedback for wideband CQIreporting (Fields for CRI feedback for wideband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and one antenna port for eachCSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

B. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for higher layer-configuredsubband CQI reporting, a bit width for CRI and RI (or RI combination)feedback may include at least one item in Table 5.2.2.6.2-3F5 and Table5.2.2.6.3-3G5:

For example, for higher layer-configured subband CQI reporting, theterminal may store at least one item in Table 5.2.2.6.2-3F5 and Table5.2.2.6.3-3G5. That is, when higher layer-configured subband CQIreporting and the first indication information are configured and thequantity of antenna ports is greater than 1, the terminal may use bitquantities of the CRI and the RI in Table 5.2.2.6.2-3F5. When higherlayer-configured subband CQI reporting is configured and the firstindication information is configured and the quantity of antenna portsis 1, the terminal may use bit quantities of the CRI and the RI in Table5.2.2.6.3-3G5.

TABLE 5.2.2.6.2-3F5 Fields for joint CRI and RI/RI Combination feedbackfor higher layer configured subband CQI reports (transmission mode 10configured with PMI/RI reporting and higher layer parameter eMIMO-Type,and eMIMO-Type is set to ‘CLASS B’ with K > 1 CSI-RS resources and morethan one port for at least one CSI-RS resource and higher layerparameter FeCoMPCSIEnabled) Bit width 4 antenna 8 antenna ports portsMax 1 Max 1 2 antenna or 2 Max 4 or 2 Max 4 Max 8 Field ports layerslayers layers layers layers CRI 2 2 2 2 2 2 Rank 2 2 4 2 4 4 indication

TABLE 5.2.2.6.3-3G5 Scenarios for CRI feedback for higherlayer-configured subband CQI reporting (Fields for CRI feedback forhigher layer configured subband CQI reports) (the transmission mode 10is configured with PMI/RI reporting and the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ configured with K > 1CSI-RS resources and one antenna port for each CSI-RS resource andconfigured with the higher layer parameter FeCoMPCSIEnabled) Field Bitwidth CRI 2

C. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for UE selected subband CQIreporting, a bit width for CRI and RI (or RI combination) feedback mayinclude at least one item in Table 5.2.2.6.3-3F6 and Table5.2.2.6.3-3G6:

For example, for UE selected subband CQI reporting, the terminal maystore at least one item in Table 5.2.2.6.3-3F6 and Table 5.2.2.6.3-3G6.That is, when UE selected subband CQI reporting and the first indicationinformation are configured and the quantity of antenna ports is greaterthan 1, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.3-3F6. When UE selected subband CQI reporting isconfigured and the first indication information is configured and thequantity of antenna ports is 1, the terminal may use bit quantities ofthe CRI and the RI in Table 5.2.2.6.3-3G6.

TABLE 5.2.2.6.3-3F6 Scenarios for joint CRI and RI/RI Combinationfeedback for UE selected subband CQI reporting (Fields for joint CRI andRI/RI Combination feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and more than one antenna portfor at least one CSI-RS resource and configured with the higher layerparameter FeCoMPCSIEnabled) Bit width 4 antenna 8 antenna ports portsMax 1 Max 1 2 antenna or 2 Max 4 or 2 Max 4 Max 8 Field ports layerslayers layers layers layers CRI 2 2 2 2 2 2 Rank 2 2 4 2 4 4 indication

In one embodiment, in Table 5.2.2.6.3-3F6, the bit width of the RI is 2,and another correspondence may be obtained by replacing the bit width ofthe RI with 3 or increasing the bit width of the RI to 3. For example,when the quantity of antenna ports is 2, the bit width of the CRI is 2,and the bit width of the RI may be 2 or 3. Similarly, when the quantityof antenna ports is 8, the capability of the terminal device is that amaximum of one layer or two layers are supported, and the RI bit widthmay be 2, 3, or the like. Specifically, whether a value is 2 or 3 may bepredefined in a protocol, or notified by the base station to theterminal. This is not specifically limited herein.

TABLE 5.2.2.6.3-3G6 Scenarios for CRI feedback for UE selected subbandCQI reporting (Fields for CRI feedback for UE selected subband CQIreports) (the transmission mode 10 is configured with PMI/RI reportingand the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ configured with K > 1 CSI-RS resources and one antenna portfor each CSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

Third implementation (namely, Method 3): The bit width of the CRI and/orthe bit width of the RI are/is determined based on the first indicationinformation and at least one of the quantity of NZP CSI-RS resources,the quantity of antenna ports for an NZP CSI-RS, the capabilityinformation of the terminal device, or the value of the CRI. In anexample, the bit width of the RI may be determined based on the firstindication information, the value of the CRI, and the quantity ofantenna ports for an NZP CSI-RS and/or the capability information of theterminal device. That is, the value of the CRI is distinguished in thiscase.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width of anRI used when a single RI is reported and/or determining a total quantityof bits occupied by a plurality of RIs (or an RI combination) when theplurality of RIs (or the RI combination) are reported. This is notspecifically limited herein.

An example in which two NZP CSI-RS resources are configured is usedbelow to describe determining the bit width of the RI based on the firstindication information, the value of the CRI, and the quantity ofantenna ports for an NZP CSI-RS and/or the capability information of theterminal device. In this case, the bit width of the CRI is 2.

In one embodiment, if a plurality of NZP CSI-RS resources areconfigured, the bit width of the RI may be determined as a maximumquantity of antenna ports for the configured NZP CSI-RS resources.

In one embodiment, for at least one of the three existing reportingmodes (wideband CQI reporting, higher layer-configured subband CQIreporting, and UE selected subband CQI reporting), respective bitquantities for CRI and/or RI feedback may be defined, or a bit width forCRI and/or RI feedback may be uniformly described. A unified descriptionmay mean that the terminal and/or the base station may store one or moreone or more mapping tables, mapping sequences, or mapping formulas fordifferent reporting modes. A separate description may mean that theterminal and/or the base station may store mapping relationships such asmapping tables, mapping sequences, or mapping formulas corresponding todifferent reporting modes.

Specifically, the reporting mode in this embodiment of the presentdisclosure may alternatively be a reporting mode in NR, 5G, or a futureresearch system. This is not specifically limited herein.

In one embodiment, when the table in this embodiment of the presentdisclosure is described, only the transmission mode 10 and configurationof a PMI/RI feedback condition are used as an example to describe thebit width of the CRI and/or the bit width of the RI. This condition ismerely an example, and may also be another condition, for example, noPMI feedback is configured. This is not specifically limited herein.

For example, for at least one of the three reporting modes, a unifieddescription manner may include at least one item in Table 5.2.2.6.1-2F3and Table 5.2.2.6.3-3G7. Table 5.2.2.6.1-2F3 shows a case in which thequantity of antenna ports is greater than 1, and Table 5.2.2.6.3-3G7shows a case in which the quantity of antenna ports is 1:

For example, for the configured first indication information and thequantity of antenna ports that is greater than 1, the terminal maydetermine the bit quantities of the CRI and the RI by using at least oneitem in Table 5.2.2.6.1-2F3. For the configured first indicationinformation and the quantity of antenna ports that is 1, the terminalmay determine the bit quantities of the CRI and the RI by using at leastone item in Table 5.2.2.6.3-3G7. For example, the terminal may store atleast one item in two tables.

TABLE 5.2.2.6.1-2F3 Scenarios for CRI and RI feedback (Fields for CRIand RI feedback) (the transmission mode 10 and the configured higherlayer parameter FeCoMPCSIEnabled) 4 antenna 8 antenna ports ports Max 1Max 1 2 antenna or 2 Max 4 or 2 Max 4 Max 8 Field ports layers layerslayers layers layers Bit width for CRI = 0 or 1 CRI 2 2 2 2 2 2 Rank 1 12 1 2 3 indication Bit width for CRI = 2 CRI 2 2 2 2 2 2 Rank 2 2 4 2 44 indication

It can be learned from Table 5.2.2.6.1-2F3 that, for example, when thequantity of antenna ports is 2, the bit width of the CRI is 2; and whenthe CRI=0 or 1, the bit width of the RI is 1; or when the CRI=2, the bitwidth of the RI is 2. Alternatively, when the quantity of antenna portsis 4 and the capability of the terminal device is that the supportedmaximum layer quantity is 4, the bit width of the CRI is 2; and when theCRI=0 or 1, the bit width of the RI is 2; or when the CRI=21, the bitwidth of the RI is 4.

TABLE 5.2.2.6.3-3G7 Scenarios for CRI feedback (Fields for CRI feedback)(the transmission mode 10 is configured with PMI/RI reporting and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ configured with K > 1 CSI-RS resources and one antenna port for eachCSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

Table 5.2.2.6.3-3G7 indicates a case in which the quantity of antennaports is 1, and the RI is not fed back. It may be considered that thebit width of the RI is 0.

The unified description manner of at least one of the three reportingmodes is described above, and a separate description manner describedbelow may be at least one of the following. Examples are as follows:

A. When FeCoMPCSIEnabled (and the aperiodic reporting mode) is (are)configured, for wideband CQI reporting, a bit width for CRI and RI (orRI combination) feedback may include at least one item in Table5.2.2.6.1-2F4:

For example, for wideband CQI reporting, the terminal may store at leastone item in Table 5.2.2.6.1-2F4 and Table 5.2.2.6.3-3G7-1. That is, whenwideband CQI reporting is configured and the first indicationinformation is configured and the quantity of antenna ports is greaterthan 1, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.1-2F4. When wideband CQI reporting is configured and thefirst indication information is configured and the quantity of antennaports is 1, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.3-3G7-1.

TABLE 5.2.2.6.1-2F4 Scenarios for CRI and RI feedback for wideband CQIreporting (Fields for CRI and RI feedback for wideband CQI reports) (thetransmission mode 10 and the configured higher layer parameterFeCoMPCSIEnabled) 4 antenna 8 antenna ports ports Max 1 Max 1 2 antennaor 2 Max 4 or 2 Max 4 Max 8 Field ports layers layers layers layerslayers Bit width for CRI = 0 or 1 CRI 2 2 2 2 2 2 Rank 1 1 2 1 2 3indication Bit width for CRI = 2 CRI 2 2 2 2 2 2 Rank 2 2 4 2 4 4indication

It can be learned from Table 5.2.2.6.1-2F4 that, for example, when thequantity of antenna ports is 2, the bit width of the CRI is 2; and whenthe CRI=0 or 1, the bit width of the RI is 1; or when the CRI=2, the bitwidth of the RI is 2. Alternatively, when the quantity of antenna portsis 4 and the capability of the terminal device is that the supportedmaximum layer quantity is 4, the bit width of the CRI is 2; and when theCRI=0 or 1, the bit width of the RI is 2; or when the CRI=21, the bitwidth of the RI is 4.

TABLE 5.2.2.6.3-3G7-1 Scenarios for CRI feedback for wideband CQIreporting (Fields for CRI feedback for wideband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with K > 1 CSI-RS resources and one antenna port for eachCSI-RS resource and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2

Table 5.2.2.6.3-3G7-1 indicates a case in which the quantity of antennaports is 1, and the RI is not fed back. It may be considered that thebit width of the RI is 0.

In the foregoing table, for example, if the quantity of antenna ports is2, when the value of the CRI is 0 or 1, the value of the RI is 1 or 2,that is, 1 bit may be used to indicate the RI. When the value of the CRIis 2, the value of the RI or a value of the RI combination is {{1, 1},{1, 2}, {2, 1}, or {2, 2}. 2 bits may be used to indicate the RI.

For example, when the quantity of antenna ports is 4, and the capabilityof the terminal device is that the supported maximum layer quantity is4, when the value of the CRI is that the CRI=0 or 1, the value of the RIis 1, 2, 3, or 4, that is, 2 bits may be used to indicate the RI (thebit width of the RI is 2). When the value of the CRI is 2, the value ofthe RI or the value of the RI combination is {1, 1}, {1, 2}, {2, 1}, {2,2}, {2, 3}, {3, 2}, {3, 3}, {3, 4}, {4, 3}, or {4, 4}. 4 bits may beused to indicate the RI (the bit width of the RI is 4).

B. When FeCoMPCSIEnabled (and the aperiodic reporting mode) is (are)configured, for higher layer-configured subband CQI reporting, a bitwidth for CRI and RI (or RI combination) feedback may include at leastone item in Table 5.2.2.6.2-3F2:

For example, for higher layer-configured subband CQI reporting, theterminal may store at least one item in Table 5.2.2.6.2-3F2 and Table5.2.2.6.3-3G7-2. That is, when higher layer-configured subband CQIreporting and the first indication information are configured and thequantity of antenna ports is greater than 1, the terminal may use bitquantities of the CRI and the RI in Table 5.2.2.6.2-3F2. When higherlayer-configured subband CQI reporting is configured and the firstindication information is configured and the quantity of antenna portsis 1, the terminal may use bit quantities of the CRI and the RI in Table5.2.2.6.3-3G7-2.

TABLE 5.2.2.6.2-3F2 Fields for CRI and RI feedback for higher layerconfigured subband CQI reports (transmission mode 10 and higher layerparameter FeCoMPCSIEnabled) 4 antenna 8 antenna ports ports Max 1 Max 12 antenna or 2 Max 4 or 2 Max 4 Max 8 Field ports layers layers layerslayers layers Bit width for CRI = 0 or 1 CRI 2 2 2 2 2 2 Rank 1 1 2 1 23 indication Bit width for CRI = 2 CRI 2 2 2 2 2 2 Rank 2 2 4 2 4 4indication

It can be learned from Table 5.2.2.6.2-3F2 that, for example, when thequantity of antenna ports is 2, the bit width of the CRI is 2; and whenthe CRI=0 or 1, the bit width of the RI is 1; or when the CRI=2, the bitwidth of the RI is 2. Alternatively, when the quantity of antenna portsis 4 and the capability of the terminal device is that the supportedmaximum layer quantity is 4, the bit width of the CRI is 2; and when theCRI=0 or 1, the bit width of the RI is 2; or when the CRI=21, the bitwidth of the RI is 4.

TABLE 5.2.2.6.3-3G7-2 Scenarios for CRI feedback for higherlayer-configured subband CQI reporting (Fields for CRI feedback forhigher layer configured subband CQI reports) (the transmission mode 10is configured with PMI/RI reporting and the higher layer parametereMIMO- Type, and eMIMO-Type is set to the ‘CLASS B’ configured with K >1 CSI-RS resources and one antenna port for each CSI-RS resource andconfigured with the higher layer parameter FeCoMPCSIEnabled(transmission mode 10 configured with PMI/RI reporting and higher layerparameter eMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with K > 1CSI-RS resources and one port for each CSI-RS resource and higher layerparameter FeCoMPCSIEnabled)) Field Bit width CRI 2

Table 5.2.2.6.3-3G7-2 indicates a case in which the quantity of antennaports is 1, and the RI is not fed back. It may be considered that thebit width of the RI is 0.

C. When FeCoMPCSIEnabled (and the aperiodic reporting mode) is (are)configured, for UE selected subband CQI reporting, a bit width for CRIand RI (or RI combination) feedback may include at least one item inTable 5.2.2.6.3-3F7 and Table 5.2.2.6.3-3G7-3:

For example, for UE selected subband CQI reporting, the terminal maystore at least one item in Table 5.2.2.6.3-3F7 and Table5.2.2.6.3-3G7-3. That is, when UE selected subband CQI reporting isconfigured and the first indication information is configured and thequantity of antenna ports is greater than 1, the terminal may use bitquantities of the CRI and the RI in Table 5.2.2.6.3-3F7. When UEselected subband CQI reporting is configured and the first indicationinformation is configured and the quantity of antenna ports is 1, theterminal may use bit quantities of the CRI and the RI in Table5.2.2.6.3-3G7-3.

TABLE 5.2.2.6.3-3F7 Scenarios for CRI and RI feedback for UE selectedsubband CQI reporting (Fields for CRI and RI feedback for UE selectedsubband CQI reports) (the transmission mode 10 and the configured higherlayer parameter FeCoMPCSIEnabled) 4 antenna 8 antenna ports ports Max 1Max 1 2 antenna or 2 Max 4 or 2 Max 4 Max 8 Field ports layers layerslayers layers layers Bit width for CRI = 0 or 1 CRI 2 2 2 2 2 2 Rank 1 12 1 2 3 indication Field Bit width for CRI = 2 CRI 2 2 2 2 2 2 Rank 2 24 2 4 4 indication

It can be learned from Table 5.2.2.6.3-3F7 that, for example, when thequantity of antenna ports is 2, the bit width of the CRI is 2; and whenthe CRI=0 or 1, the bit width of the RI is 1; or when the CRI=2, the bitwidth of the RI is 2. Alternatively, when the quantity of antenna portsis 4 and the capability of the terminal device is that the supportedmaximum layer quantity is 4, the bit width of the CRI is 2; and when theCRI=0 or 1, the bit width of the RI is 2; or when the CRI=21, the bitwidth of the RI is 4.

TABLE 5.2.2.6.3-3G7-3 Scenarios for CRI feedback for higherlayer-configured subband CQI reporting (Fields for CRI feedback forhigher layer configured subband CQI reports) (the transmission mode 10is configured with PMI/RI reporting and the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ configured with K > 1CSI-RS resources and one antenna port for each CSI-RS resource andconfigured with the higher layer parameter FeCoMPCSIEnabled) Field Bitwidth CRI 2

Table 5.2.2.6.3-3G7-3 indicates a case in which the quantity of antennaports is 1, and the RI is not fed back. It may be considered that thebit width of the RI is 0.

Fourth implementation (namely, Method 4): At least one of the bit widthof the CRI or the bit width of the RI is determined based on the firstindication information and at least one of the quantity of NZP CSI-RSresources, the quantity of antenna ports for an NZP CSI-RS, thecapability information of the terminal device, or the value of the CRI.In an example, the bit width of the RI may be determined based on thefirst indication information and the value of the CRI.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width of anRI used when a single RI is reported and/or determining a total quantityof bits occupied by a plurality of RIs (or an RI combination) when theplurality of RIs (or the RI combination) are reported. This is notspecifically limited herein.

An example in which two NZP CSI-RS resources are configured is usedbelow to describe how to determine the bit width of the RI based on thefirst indication information and the value of the CRI. In this case, thebit width of the CRI is 2.

In one embodiment, for at least one of the three existing reportingmodes (wideband CQI reporting, higher layer-configured subband CQIreporting, and UE selected subband CQI reporting), respective bitquantities for CRI and/or RI feedback may be defined, or a bit width forCRI and/or RI feedback may be uniformly described. A unified descriptionand a separate description may mean that the terminal and/or the basestation may store one or more mapping tables, mapping sequences, ormapping formulas for different reporting modes, or may store respectivemapping tables, mapping sequences, or mapping formulas.

Specifically, the reporting mode in this embodiment of the presentdisclosure may alternatively be a reporting mode in NR, 5G, or a futureresearch system. This is not specifically limited herein.

In this embodiment of the present disclosure, a transmission mode 10 isused as an example in the table. That is, FeCoMP-based CSI measurementand/or feedback can be applied only to a terminal in the transmissionmode 10 in an LTE system, but is not applicable to another transmissionmode in the LTE system. In this embodiment of the present disclosure,FeCoMP-based CSI measurement and/or feedback are/is also applicable to atransmission mode in NR, 5G, or a future communications system, and isnot limited to the transmission mode 10. In this case, the transmissionmode 10 is merely an example, and another transmission mode is notlimited herein. Alternatively, FeCoMP-based CSI measurement and/orfeedback are/is also applicable to any transmission mode, that is,FeCoMP-based CSI measurement and/or feedback are/is unrelated to atransmission mode.

For example, for at least one of the three reporting modes, a unifieddescription manner includes at least one item in Table 5.2.2.6.1-2F5:

When the terminal configures the transmission mode 10 and the higherlayer parameter FeCoMPCSIEnabled, a bit width for CRI and RI feedback isshown in Table 5.2.2.6.3-3F. The terminal may store only one mappingtable, mapping sequence, or mapping formula.

TABLE 5.2.2.6.1-2F5 Scenarios for CRI and RI feedback (Fields for CRIand RI feedback) (the transmission mode 10 and the configured higherlayer parameter FeCoMPCSIEnabled) Field Bit width CRI 2 Rank indicationfor CRI = 0, 1 3 Rank indication for CRI = 2 4

It can be learned from Table 5.2.2.6.1-2F5 that, when the terminalconfigures the higher layer parameter FeCoMPCSIEnabled, for at least oneof the three reporting modes, the bit width of the CRI is 2; and whenthe CRI=0 or 1, the bit width of the RI is 3; or when the CRI=2, the bitwidth of the RI is 4. The value of the CRI and the value of the bitwidth of the RI are merely examples herein, or may be other values. Thisis not specifically limited herein.

For example, for at least one of the three reporting modes, a separatedescription manner may be at least one of the following:

A. When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), for wideband CQI reporting, abit width for CRI and RI (or RI combination) feedback is fixed, and atleast one item in Table 5.2.2.6.1-2F6 may be included. For example, forwideband CQI reporting, the terminal may store Table 5.2.2.6.1-2F6, thatis, when wideband CQI reporting and the first indication information areconfigured, the terminal may use bit quantities of the CRI and the RI inTable 5.2.2.6.1-2F6.

TABLE 5.2.2.6.1-2F6 Scenarios for CRI and RI feedback for wideband CQIreporting (Fields for CRI and RI feedback for wideband CQI reports) (thetransmission mode 10 and the configured higher layer parameterFeCoMPCSIEnabled) Field Bit width CRI 2 Rank indication for CRI = 0, 1 3Rank indication for CRI = 2 4

It can be learned from Table 5.2.2.6.1-2F6 that, when the terminalconfigures the higher layer parameter FeCoMPCSIEnabled, for the widebandCQI reporting mode, the bit width (also referred to as a bit width or abit length) of the CRI is 2; and when the CRI=0 or 1, the bit width ofthe RI is 3; or when the CRI=2, the bit width of the RI is 4. The valueof the CRI and the value of the bit width of the RI are merely examplesherein, or may be other values. This is not specifically limited herein.

B. When FeCoMPCSIEnabled (and the aperiodic reporting mode) is (are)configured, for subband CQI reporting, a bit width for CRI and RI (or RIcombination) feedback is fixed, and at least one item in Table5.2.2.6.2-3F3 may be included. For example, for higher layer-configuredsubband CQI reporting, the terminal may store Table 5.2.2.6.2-3F3, thatis, when higher layer-configured subband CQI reporting and the firstindication information are configured, the terminal may use bitquantities of the CRI and the RI in Table 5.2.2.6.2-3F3.

TABLE 5.2.2.6.2-3F3 Scenarios for CRI and RI feedback for higherlayer-configured subband CQI reporting (Fields for CRI and RI feedbackfor higher layer configured subband CQI reports) (the transmission mode10 and the configured higher layer parameter FeCoMPCSIEnabled) Field Bitwidth CRI 2 Rank indication for CRI = 0, 1 3 Rank indication for CRI = 24

It can be learned from Table 5.2.2.6.2-3F3 that, when the terminalconfigures the higher layer parameter FeCoMPCSIEnabled, for the higherlayer-configured subband CQI reporting mode, the bit width of the CRI is2; and when the CRI=0 or 1, the bit width of the RI is 3; or when theCRI=2, the bit width of the RI is 4. The value of the CRI and the valueof the bit width of the RI are merely examples herein, or may be othervalues. This is not specifically limited herein.

C. When FeCoMPCSIEnabled (and the aperiodic reporting mode) is (are)configured, for UE selected subband CQI reporting, a bit width for CRIand RI (or RI combination) feedback is fixed, and at least one item inTable 5.2.2.6.3-3F8 may be included. For example, for UE selectedsubband CQI reporting, the terminal may store Table 5.2.2.6.3-3F8, thatis, when UE selected subband CQI reporting and the first indicationinformation are configured, the terminal may use bit quantities of theCRI and the RI in Table 5.2.2.6.3-3F8.

TABLE 5.2.2.6.3-3F8 Scenarios for CRI and RI feedback for UE selectedsubband CQI reporting (Fields for CRI and RI feedback for UE selectedsubband CQI reports) (the transmission mode 10 and the configured higherlayer parameter FeCoMPCSIEnabled) Field Bit width CRI 2 RI indicationfor CRI = 0, 1 3 RI indication for CRI = 2 4

It can be learned from Table 5.2.2.6.3-3F8 that, when the terminalconfigures the higher layer parameter FeCoMPCSIEnabled, for the higherlayer-configured subband CQI reporting mode, the bit width of the CRI is2; and when the CRI=0 or 1, the bit width of the RI is 3; or when theCRI=2, the bit width of the RI is 4. The value of the CRI and the valueof the bit width of the RI are merely examples herein, or may be othervalues. This is not specifically limited herein.

In the foregoing implementation, the CRI and the RI are jointly encoded,or the CRI and the RI are independently encoded.

The following provides the fifth implementation. In this implementation,if the CSI includes at least two RIs, the CRI and at least one of theRIs are jointly encoded, and a remaining RI is not jointly encoded withthe CRI.

This embodiment may be an independent embodiment, or may be combinedwith another embodiment. This is not specifically limited herein.

In this embodiment of the present disclosure, the CSI feedback relatedinformation is determined based on the first indication information,where the CSI feedback related information includes the coding schemefor the CRI and the RI. In the fifth implementation, the coding schemefor the CRI and the RI is that the CSI includes at least two RIs, theCRI and at least one of the RIs are jointly encoded, and a remaining RIis independently encoded.

In one embodiment, that the CSI includes at least two RIs, the CRI andat least one of the RIs are jointly encoded, and a remaining RI isindependently encoded may mean that the CRI and one of the RIs arejointly encoded, and the remaining RI changes independently, or may meanthat the CRI and two of the RIs are jointly encoded, and the remainingRI changes independently. Another case is also applicable. This is notlimited herein.

Further, in one embodiment, in this embodiment of the presentdisclosure, for the remaining RI, it may be determined, based on thevalue of the CRI, whether there is an RI other than the at least one RI(namely, the RI that is jointly encoded with the CRI).

Specifically, an example in which two NZP CSI-RS resources areconfigured is used. That is, an example in which the CRI is of 2 bits isused to describe how to determine, based on the value of the CRI,whether there are an RI other than the at least one RI.

Two NZP CSI-RS resources are configured. In this case, a meaning of CRImay be shown as follows:

The CRI=0 represents CSI measurement and feedback based on the first NZPCSI-RS resource.

The CRI=1 represents CSI measurement and feedback based on the secondNZP CSI-RS resource.

The CRI=2 represents CSI measurement and feedback based on the first NZPCSI-RS resource and the second NZP CSI-RS.

When the CRI=0 or 1, CSI measurement and feedback in the prior art maybe performed. For example, a set of CSI is fed back, where the CSI mayinclude at least one of an RI, a PMI, and a CQI.

When the CRI=2, two sets of CSI need to be fed back. The first set ofCSI may be CSI corresponding to the first NZP CSI-RS resource, and thesecond set of CSI may be CSI corresponding to the second NZP CSI-RSresource.

In one embodiment, the first set of CSI corresponds to CSI for the firstcodeword (for example, a codeword 0), and the second set of CSIcorresponds to CSI for the second codeword.

In one embodiment, each set of CSI may include at least one of an RI, aPMI, and a CQI.

In one embodiment, when the CRI=2, inter-stream interference orinter-codeword interference in two NZP CSI-RS resources needs to beconsidered when the CQI is calculated.

Specifically, it is determined, based on the value of the CRI, whetherthere are an RI other than the at least one RI. An example is asfollows:

For example, when the CRI=0 or 1, there is only at least one RI, and theat least one RI is an RI obtained through measurement based on an NZPCSI-RS resource corresponding to the value of the CRI. When the CRI=2,there is also a remaining RI other than the at least one RI.

In this case, the network device and/or the terminal device may receivethe RI based on the value of the CRI, including whether to receive theremaining RI other than the at least one RI.

Further, in one embodiment, a quantity of remaining RIs other than theat least one RI may be further determined based on the value of the CRI.The quantity of remaining RIs may be an integer greater than or equal to0, for example, 0, 1, or 2. This is not specifically limited herein.

In this embodiment of the present disclosure, when a quantity of RIs is2 or RI feedback is RI combination feedback, the at least one RI is anRI obtained through measurement based on the first NZP CSI-RS resource,and the remaining RI is an RI obtained through measurement based on thesecond NZP CSI-RS resource.

Alternatively, the at least one RI may be an RI corresponding to the CSIfor the first codeword, and the remaining RI is an RI corresponding theCSI for the second codeword. Alternatively, the at least one RI is an RIcorresponding to the first set of CSI, and the remaining RI is an RIcorresponding to the second set of CSI.

Correspondingly, the fifth implementation (namely, Method 5) ofdetermining the bit width of the CRI and/or the bit width of the RI maybe:

determining the bit width of the CRI and/or the bit width of the RIbased on the first indication information and at least one of thequantity of NZP CSI-RS resources, the quantity of antenna ports for anNZP CSI-RS, the capability information of the terminal device, or thevalue of the CRI.

A CRI and at least one RI in CSI in coordinated multipointtransmission/reception mode (or FeCoMP or hybrid transmission mode ornon-coherent transmission mode)-based CSI measurement and/or feedbackare jointly encoded, and whether there is a remaining RI may bedetermined based on a value of the CRI. In one embodiment, if there is aremaining RI, the remaining RI is not jointly encoded with CRI.

For example, if the CRI=0 or 1 is fed back/received, it is determinedthat there is no remaining RI, or if the CRI=2 is fed back/received, itis determined that there is a remaining RI.

In this embodiment of the present disclosure, when the CRI and the atleast one RI are jointly encoded, a method for determining the bit widthof the RI includes at least one of the following:

In one embodiment, the bit width of the RI may be a bit width of an RIthat is jointly encoded with the CRI.

Specifically, for example, when the value of the CRI is 0, the CRI maycorrespond to an RI of the first NZP CSI-RS resource. When the value ofthe CRI is 1, the CRI may correspond to an RI of the second NZP CSI-RSresource; or when the value of the CRI is 2, the CRI may correspond toan RI of the first NZP CSI-RS resource.

Specifically, the following methods A to G may be used for determining.

Method A: The bit width of the RI may be determined based on a maximumquantity of antenna ports for two NZP CSI-RS resources and/or thecapability information of the terminal device. For example, the bitwidth of the RI may be determined by using a solution in the prior art,and another manner is not limited either. Details are not describedherein.

However, if the maximum quantity of antenna ports for the two NZP CSI-RSresources is 1, the RI does not need to be fed back.

Method B: The bit width of the RI may be determined based on the firstindication information. For example, when receiving the first indicationinformation, the terminal may determine, based on the first indicationinformation, that the bit width of the RI is fixed, for example, fixedto 3. A value range of the RI may be [1, 8]. For example, the bit widthof the RI is fixed to 2, and the value range of the RI is [1, 4]. Aspecific value is merely an example herein, and the value may bepredefined in a protocol, or notified by the base station to theterminal. This is not specifically limited herein.

In this embodiment of the present disclosure, a method for determining abit width of an independently encoded RI may include at least one of thefollowing:

In one embodiment, the bit width of the independently encoded RI may bea bit width of the RI corresponding to the second NZP CSI-RS resource,or may be a bit width of the second RI in a plurality of RIs, or may bea bit width of the second RI in an RI combination. A meaning ofindependent encoding is correspondingly explained in another part, anddetails are not described herein again.

Method C: The bit width of the RI may be determined based on a maximumvalue of quantities of antenna ports for two NZP CSI-RS resources and/orthe capability information of the terminal device.

Method D: The bit width of the RI may be determined based on a quantityof antenna ports for the second NZP CSI-RS resource (namely, an NZPCSI-RS resource corresponding to the remaining RI).

Method E: The bit width of the RI may be determined based on the firstindication information. For example, when receiving the first indicationinformation, the terminal may determine, based on the first indicationinformation, that the bit width of the RI is fixed, for example, fixedto 2.

In one embodiment, for coordinated multipoint transmission/reception orFeCoMP or hybrid transmission mode-based CSI measurement and/orfeedback, when two RIs are fed back, a combination of the two RIs islimited, and a limitation is {RI 1, RI 2}={1, 1}, {1, 2}, {2, 1}, {2,2}, {2, 3}, {3, 2}, {3, 3}, {3, 4}, {4, 3}, or {4, 4}.

That is, values of the two RIs are equal or have a difference of 1.Therefore, three states may be indicated by using two bits. For example,a state 0 indicates that a value of each one of the at least one RI isequal to a value of a remaining RI, that is, the difference is 0. Astate 1 indicates that a value of a remaining RI is less than a value ofthe at least one RI by 1, that is, the difference is −1. A state 2indicates that a value of a remaining RI is greater than a value of theat least one RI by 1, that is, the difference is 1. For example, bits 00represent the state 0, bits 01 represent the state 1, and bits 10represent the state 2. Certainly, the state meaning and the state numberherein are merely examples, and there may be another correspondence. Acorrespondence manner between the bit meaning and the state is alsomerely an example, and there may be another correspondence. For example,2 bits may be used to indicate a bit meaning of an independently encodedRI. In one embodiment, the 2-bit meaning may be at least one item shownin the following table:

TABLE 5.2.2.6-6A1-3 O₀ ^(RI), O₁ ^(RI) to RI mapping O₀ ^(RI), O₁ ^(RI)ΔRI 0, 0 0 0, 1 −1 1, 0 1 1, 1 Reserved

A value of ΔRI may be fed back based on what is shown in the table. IfΔRI=0, it indicates that a value of the second RI is equal to a value ofthe first RI; if ΔRI=−1, it indicates that a value of the second RI isless than a value of the first RI by 1. For example, if the value of thefirst RI is 2, the second RI value may be determined as 1 based on thevalue of the first RI and a value of ΔRI. If ΔRI=1, it indicates that avalue of the second RI is greater than the value of the first RI by 1.For example, if the value of the first RI is 2, the second RI value maybe determined as 3 based on the value of the first RI and the value ofΔRI. The values in the table in this embodiment of the presentdisclosure are merely examples, a correspondence between a bit value anda feedback variable value is also merely an example, and another valueor correspondence is also feasible. This is not specifically limitedherein.

Method F: Determining is performed based on a quantity of antenna portsfor the second NZP CSI-RS resource and a rule that a maximum bit widthof the RI is 2, that is, a larger value is selected from 2 and the bitwidth of the RI that is determined based on the quantity of antennaports for the second NZP CSI-RS resource.

Method G: The bit width of the RI is fixed, for example, fixed to 3. Avalue range of the RI may be [1, 8].

A plurality of RIs are mentioned above, that is, a sequence of the RIsis involved. For example, if two RIs are determined to be fed back, asequence of the RIs may be predefined in a protocol, or a sequence ofthe RIs may be configured by the network device.

For example, the predefined sequence of the RIs is that at least one RIcorresponds to the first NZP CSI-RS resource, and a remaining RIcorresponds to the second NZP CSI-RS resource, or the sequence of theRIs is determined based on an identifier of an NZP CSI-RS resource or anidentifier of a resource set.

Determining of the bit meaning of the RI is described below.

This embodiment provides a method for determining the bit meaning of theRI. The method may be combined with the method for determining the bitwidth of the RI in the first implementation (Method 1) or Method 2.1 inthe second implementation (Method 2) or the fourth implementation(Method 4). A manner of determining bit mapping of the RI, namely, thebit meaning of the RI may include one of the following implementations.

-   -   Implementation 1 (or referred to as Method 1.1): The bit meaning        of the RI is determined based on the first indication        information.

In this embodiment of the present disclosure, when receiving the firstindication information, the terminal may determine the bit meaning ofthe RI based on the first indication information. For example, aspecific bit meaning may be at least one item in Table 5.2.2.6-8-1.

When FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and theaperiodic reporting mode are configured), a bit meaning of RI (or RIcombination) feedback may include at least one item in Table5.2.2.6-8-1:

TABLE 5.2.2.6-8-1 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mappingo₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI/RI combination 0, 0, 0, 0 1 0,0, 0, 1 2 0, 0, 1, 0 3 0, 0, 1, 1 4 0, 1, 0, 0 5 0, 1, 0, 1 6 0, 1, 1, 0{1, 1} 0, 1, 1, 1 {1, 2} 1, 0, 0, 0 {2, 1} 1, 0, 0, 1 {2, 2} 1, 0, 1, 0{2, 3} 1, 0, 1, 1 {3, 2} 1, 1, 0, 0 {3, 3} 1, 1, 0, 1 {3, 4} 1, 1, 1, 0{4, 3} 1, 1, 1, 1 {4, 4}

In Table 5.2.2.6-8-1, an example in which the bit width of the RI is 4is used, and o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), and o₃ ^(RI) indicate 4 bitsof the RI. For example, when the 4 bits of the RI are 0000, itcorresponds to one RI, and a value of the RI is 1; or when the 4 bits ofthe RI are 1000, it corresponds to two RIs or one RI combination, andvalues of the two RIs are respectively 2 and 1, or a value of the RIcombination is {2, 1}, that is, the RI 1=2, and the RI 2=1. A case ofanother bit width of the RI is similar to this. This is not specificallylimited herein.

-   -   Implementation 2 (or referred to as Method 1.2): The bit meaning        of the RI is determined based on the first indication        information and the value of the CRI.

When the first indication information is set to FeCoMPCSIEnabled or avalue of FeCoMPCSIEnabled is TRUE, the bit width of the RI may bedetermined, for example, is 4.

In view of this, Implementation 2 (namely, Method 1.2) may also beunderstood as follows: The bit meaning of the RI is determined based onthe bit width of the RI and the value of the CRI. In other words, thedetermining the bit meaning of the RI based on the first indicationinformation and a value of the CRI includes: determining the bit widthof the RI based on the first indication information, and furtherdetermining the bit meaning of the RI based on the bit width of the RIand the value of the CRI.

Therefore, when FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled andthe aperiodic reporting mode are configured), or when the bit width ofthe RI is a specific value such as 4, a bit meaning of RI (or RIcombination) feedback is described below. Herein, an example in whichthe bit width of the RI is 4 is used for description. When the bit widthof the RI is another value, a similar design may also be used:

If the CRI=0 or 1, the mapping mode may include at least one item inTable X21.

TABLE X21 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mapping o₀ ^(RI),o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI 0, 0, 0, 0 1 0, 0, 0, 1 2 0, 0, 1, 0 30, 0, 1, 1 4 0, 1, 0, 0 5 0, 1, 0, 1 6 0, 1, 1, 0 7 0, 1, 1, 1 8 1, 0,0, 0 Reserved 1, 0, 0, 1 Reserved 1, 0, 1, 0 Reserved 1, 0, 1, 1Reserved 1, 1, 0, 0 Reserved 1, 1, 0, 1 Reserved 1, 1, 1, 0 Reserved 1,1, 1, 1 Reserved

The CRI=0 indicates that the value of the CRI is 0, which is similar tothe following. It can be learned from Table X21 that, if the value ofthe CRI is 0 or 1, and 4 bits occupied by the RI are 0000, itcorresponds to one RI, and a value of the RI is 1. Alternatively, it maycorrespond to one RI combination, and a value of the RI combination is{1, 0}, that is, a value of the first RI is 1, and a value of the secondRI is 0; or it may be considered that the second RI does not exist.Other rows have similar explanations, and it may also be applicable tosimilar cases in other parts.

If the CRI=2, the mapping mode may include at least one item in TableX31.

TABLE X31 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI/RI combinationmapping o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI/RI combination 0, 0,0, 0 {1, 1} 0, 0, 0, 1 {1, 2} 0, 0, 1, 0 {2, 1} 0, 0, 1, 1 {2, 2} 0, 1,0, 0 {2, 3} 0, 1, 0, 1 {3, 2} 0, 1, 1, 0 {3, 3} 0, 1, 1, 1 {3, 4} 1, 0,0, 0 {4, 3} 1, 0, 0, 1 {4, 4} 1, 0, 1, 0 Reserved 1, 0, 1, 1 Reserved 1,1, 0, 0 Reserved 1, 1, 0, 1 Reserved 1, 1, 1, 0 Reserved 1, 1, 1, 1Reserved

It can be learned from Table X31 that, if the value of the CRI is 2, and4 bits occupied by the RI are 0000, it corresponds to two RIs, andvalues of the two RIs are both 1. Other rows have similar explanations.

Alternatively, the CRI=0, 1, or 2 may be indicated by one table, and themapping mode may include at least one item in Table X31-1.

TABLE X31-1 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI/RI combinationmapping RI/RI combination for RI/RI combination for o₀ ^(RI), o₁ ^(RI),o₂ ^(RI), o₃ ^(RI) CRI = 0, or 1 CRI = 2 0, 0, 0, 0 1 {1, 1} 0, 0, 0, 12 {1, 2} 0, 0, 1, 0 3 {2, 1} 0, 0, 1, 1 4 {2, 2} 0, 1, 0, 0 5 {2, 3} 0,1, 0, 1 6 {3, 2} 0, 1, 1, 0 7 {3, 3} 0, 1, 1, 1 8 {3, 4} 1, 0, 0, 0Reserved {4, 3} 1, 0, 0, 1 Reserved {4, 4} 1, 0, 1, 0 Reserved Reserved1, 0, 1, 1 Reserved Reserved 1, 1, 0, 0 Reserved Reserved 1, 1, 0, 1Reserved Reserved 1, 1, 1, 0 Reserved Reserved 1, 1, 1, 1 ReservedReserved

Alternatively,

if the CRI=0 or 1, only one RI is fed back, and the mapping mode mayinclude at least one item in Table X22.

TABLE X22 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mapping o₀ ^(RI),o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI 0, 0, 0, 0 1 0, 0, 0, 1 2 0, 0, 1, 0 30, 0, 1, 1 4 0, 1, 0, 0 5 0, 1, 0, 1 6 0, 1, 1, 0 7 0, 1, 1, 1 8 1, 0,0, 0 Reserved 1, 0, 0, 1 Reserved 1, 0, 1, 0 Reserved 1, 0, 1, 1Reserved 1, 1, 0, 0 Reserved 1, 1, 0, 1 Reserved 1, 1, 1, 0 Reserved 1,1, 1, 1 Reserved

If the CRI=2, two RIs are fed back, and the mapping mode may include atleast one item in Table X33.

TABLE X33 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mapping o₀ ^(RI),o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI 1 RI 2 0, 0, 0, 0 1 1 0, 0, 0, 1 1 2 0,0, 1, 0 2 1 0, 0, 1, 1 2 2 0, 1, 0, 0 2 3 0, 1, 0, 1 3 2 0, 1, 1, 0 3 30, 1, 1, 1 3 4 1, 0, 0, 0 4 3 1, 0, 0, 1 4 4 1, 0, 1, 0 ReservedReserved 1, 0, 1, 1 Reserved Reserved 1, 1, 0, 0 Reserved Reserved 1, 1,0, 1 Reserved Reserved 1, 1, 1, 0 Reserved Reserved 1, 1, 1, 1 ReservedReserved

The RI 1 and the RI 2 represent the two RIs that are fed back.

In all of Table X21, Table X31, Table X31-1, Table X22, and Table X33above, 4 bits are used to indicate a value of one RI or values of twoRIs, and a joint indication manner is used. The following describesanother manner. To be specific, 4 bits of the RI may be split into twoparts each including 2 bits. This is equivalent to using two bits toindicate one RI.

For example, for the CRI=2, a mapping mode of 2 bits in the 4 bits ofthe RI may include at least one item in Table 5.2.2.6-6A, and a 4-bit RImapping mode may be obtained by combining two 2-bit mapping modes:

TABLE 5.2.2.6-6A O₀ ^(RI), O₁ ^(RI) to RI mapping O₀ ^(RI), O₁ ^(RI) RI0, 0 1 0, 1 2 1, 0 3 1, 1 4

In this embodiment of the present disclosure, a correspondence between avalue of at least one of the bits o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), and o₃^(RI) and the value of the RI is merely an example, and anothercorrespondence is also applicable. This is not specifically limitedherein.

This embodiment provides another method for determining the bit meaningof the RI. The determining method may be combined with another methodfor determining the bit width of the RI in this embodiment, for example,combined with the method for determining the bit width of the RI inMethod 2.2 or Method 3, or may be combined with another method fordetermining the bit width of the RI. Details are not described herein.

In one embodiment, in this embodiment of the present disclosure, thedetermining the bit width of the RI may be determining a bit width of anRI used when a single RI is reported and/or determining a total quantityof bits occupied by a plurality of RIs (or an RI combination) when theplurality of RIs (or the RI combination) are reported. This is notspecifically limited herein.

This embodiment may be independently implemented, or may be applied incombination with another embodiment. This is not specifically limitedherein.

A. A Case in which the Bit Width of the RI is 2:

The bit meaning of the CRI and/or the bit meaning of the RI are/isdetermined based on the first indication information and at least one ofthe quantity of NZP CSI-RS resources, the quantity of antenna ports foran NZP CSI-RS, the capability information of the terminal device, thebit width of the RI, or the value of the CRI. In an example, the bitmeaning of the RI may be determined based on the value of the CRI, thefirst indication information, and at least one of the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the bit width of the RI.

In one embodiment, the terminal determines the bit meaning of the RIbased on the quantity of antenna ports for an NZP CSI-RS resource, thevalue of the CRI, and the first indication information. For example, theterminal may determine the bit width of the RI based on the quantity ofantenna ports for an NZP CSI-RS resource, and then determine the bitmeaning of the RI based on the bit width of the RI, the value of theCRI, and the first indication information.

In one embodiment, the terminal determines the bit meaning of the RIbased on the quantity of antenna ports for an NZP CSI-RS resource, thecapability information of the terminal device, the value of the CRI, andthe first indication information. For example, the terminal maydetermine the bit width of the RI based on the quantity of antenna portsfor an NZP CSI-RS resource and the capability information of theterminal device, and then determine the bit meaning of the RI based onthe bit width of the RI, the value of the CRI, and the first indicationinformation.

In one embodiment, the terminal determines the bit meaning of the RIbased on the bit width of the RI, the value of the CRI, and the firstindication information.

For example, the terminal may determine the bit width of the RI, forexample, as 2 bits, based on the first indication information and atleast one of the quantity of antenna ports for an NZP CSI-RS resourceand the capability information of the terminal device, and determine thebit meaning of the RI based on the value of the CRI and the firstindication information. An example is as follows:

For example, when FeCoMPCSIEnabled (and the aperiodic reporting mode) is(are) configured, a bit meaning of RI (or RI combination) feedback is asfollows:

When the CRI=0 or 1, the mapping mode may include at least one item inTable 5.2.2.6-6A1.

When the CRI=0 or 1, the bit meaning of the RI may mean that one RI isfed back.

TABLE 5.2.2.6-6A1 O₀ ^(RI), to O₁ ^(RI) mapping for CRI = 0, 1 O₀ ^(RI),O₁ ^(RI) RI 0, 0 1 0, 1 2 1, 0 3 1, 1 4

Alternatively, when the CRI=2, the mapping mode may include at least oneitem in Table 5.2.2.6-6A2.

When the CRI=2, the bit meaning of the RI may mean that two RIs are fedback or an RI combination is fed back.

TABLE 5.2.2.6-6A2 o₀ ^(RI), o₁ ^(RI) to RI mapping for CRI = 2 o₀ ^(RI),o₁ ^(RI) RI/RI combination 0, 0 {1, 1} 0, 1 {1, 2} 1, 0 {2, 1} 1, 1 {2,2}

Alternatively, the CRI=0, 1, or 2 may be indicated by one table, forexample, at least one item in the following Table 5.2.2.6-6A2-1.

When the CRI=0 or 1, the bit meaning of the RI may mean that one RI isfed back.

When the CRI=2, the bit meaning of the RI may mean that two RIs are fedback or an RI combination is fed back.

TABLE 5.2.2.6-6A2-1 o₀ ^(RI), o₁ ^(RI) to RI mapping for CRI = 2 RI forCRI = RI/RI combination o₀ ^(RI), o₁ ^(RI) 0 or 1 for CRI = 2 0, 0 1 {1,1} 0, 1 2 {1, 2} 1, 0 3 {2, 1} 1, 1 4 {2, 2}

Alternatively, when the CRI=2, the mapping mode may include at least oneitem in Table 5.2.2.6-6A3.

When the CRI=2, the bit meaning of the RI may mean that two RIs are fedback or an RI combination is fed back.

TABLE 5.2.2.6-6A3 o₀ ^(RI), o₁ ^(RI) to RI mapping for CRI = 2 o₀ ^(RI),o₁ ^(RI) RI 1 RI 2 0, 0 1 1 0, 1 1 2 1, 0 2 1 1, 1 2 2

Alternatively, when the CRI=2, the mapping mode may include at least oneitem in Table 5.2.2.6-6A4. In Table 5.2.2.6-6A4, 2 bits of the RI aresplit into two parts each including 1 bit, and a mapping mode of eachbit may include at least one item in Table 5.2.2.6-6A4:

TABLE 5.2.2.6-6A4 o₀ ^(RI) or o₁ ^(RI) to RI mapping for CRI = 2 o₀^(RI), o₁ ^(RI) RI 0 1 1 2

In one embodiment, the terminal may store at least one item in theforegoing table, and determine the bit width of the RI, for example, 2,based on the first indication information and at least one of thequantity of antenna ports for an NZP CSI-RS resource and the capabilityinformation of the terminal device, and determine the bit meaning of theRI from the foregoing table based on the value of the CRI and the firstindication information. It may be understood that, when the bit width ofthe RI is determined as 2 in another manner, the foregoing bit meaningof the RI is also applicable.

B. A Case in which the Bit Width of the RI is 3:

At least one of the bit meaning of the CRI or the bit meaning of the RIis determined based on the first indication information and at least oneof the quantity of NZP CSI-RS resources, the quantity of antenna portsfor an NZP CSI-RS, the capability information of the terminal device,the bit width of the RI, or the value of the CRI. In an example, the bitmeaning of the RI may be determined based on the first indicationinformation and the bit width of the RI.

In one embodiment, when FeCoMPCSIEnabled is configured (orFeCoMPCSIEnabled and the aperiodic reporting mode are configured), whenthe bit width of the RI is 3, a bit meaning of RI (or RI combination)feedback may include at least one item in Table 5.2.2.6-8-2:

TABLE 5.2.2.6-8-2 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI) to RI mapping o₀ ^(RI),o₁ ^(RI), o₂ ^(RI) RI/RI combination 0, 0, 0 1 0, 0, 1 2 0, 1, 0 {1, 1}0, 1, 1 {1, 2} 1, 0, 0 {2, 1} 1, 0, 1 {2, 2} 1, 1, 0 Reserved 1, 1, 1Reserved

In one embodiment, the terminal may store at least one item in theforegoing table, and determine the bit width of the RI, for example, 3,based on the first indication information and at least one of thequantity of antenna ports for an NZP CSI-RS resource and the capabilityinformation of the terminal device, and determine the bit meaning of theRI from the foregoing table based on the bit width of the RI and thefirst indication information. It may be understood that, when the bitwidth of the RI is determined as 3 in another manner, the foregoing bitmeaning of the RI is also applicable.

C. A Case in which the Bit Width of the RI is 4:

Possible Manner 1:

At least one of the bit meaning of the CRI or the bit meaning of the RIis determined based on the first indication information and at least oneof the quantity of NZP CSI-RS resources, the quantity of antenna portsfor an NZP CSI-RS, the capability information of the terminal device,the bit width of the RI, or the value of the CRI. In an example, the bitmeaning of the RI may be determined based on the value of the CRI, thefirst indication information, and at least one of the quantity ofantenna ports for an NZP CSI-RS, the capability information of theterminal device, or the bit width of the RI. For example, whenFeCoMPCSIEnabled is configured (or FeCoMPCSIEnabled and the aperiodicreporting mode are configured), a bit meaning of RI (or RI combination)feedback is as follows:

When the CRI=0 or 1, the mapping mode may include at least one item inTable X24.

When the CRI=0 or 1, the bit meaning of the RI may mean that one RI isfed back.

TABLE X24 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mapping for CRI =0, 1 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI/RI combination 0, 0, 0, 01 0, 0, 0, 1 2 0, 0, 1, 0 3 0, 0, 1, 1 4 0, 1, 0, 0 5 0, 1, 0, 1 6 0, 1,1, 0 7 0, 1, 1, 1 8 1, 0, 0, 0 Reserved 1, 0, 0, 1 Reserved 1, 0, 1, 0Reserved 1, 0, 1, 1 Reserved 1, 1, 0, 0 Reserved 1, 1, 0, 1 Reserved 1,1, 1, 0 Reserved 1, 1, 1, 1 Reserved

Alternatively, when the CRI=0 or 2, the mapping mode may include atleast one item in Table X34.

When the CRI=2, the bit meaning of the RI may mean that two RIs are fedback or an RI combination is fed back.

TABLE X34 o₀ ^(R1), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mapping for CRI =2 o₀ ^(R1), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI/RI combination 0, 0, 0, 0{1, 1} 0, 0, 0, 1 {1, 2} 0, 0, 1, 0 {2, 1} 0, 0, 1, 1 {2, 2} 0, 1, 0, 0{2, 3} 0, 1, 0, 1 {3, 2} 0, 1, 1, 0 {3, 3} 0, 1, 1, 1 {3, 4} 1, 0, 0, 0{4, 3} 1, 0, 0, 1 {4, 4} 1, 0, 1, 0 Reserved 1, 0, 1, 1 Reserved 1, 1,0, 0 Reserved 1, 1, 0, 1 Reserved 1, 1, 1, 0 Reserved 1, 1, 1, 1Reserved

Alternatively, the CRI=0, 1, or 2 may be indicated by one table, and themapping mode may include at least one item in Table X34-1.

In this case, in one embodiment, the terminal determines the bit meaningof the RI based on the bit width of the RI and the value of the CRI.Specifically, for example, the terminal determines that the bit width ofthe RI is 4, and then may determine the bit meaning of the RI based onthe value of the CRI, which, for example, may be at least one item thefollowing Table X34-1.

When the CRI=0 or 1, the bit meaning of the RI may mean that one RI isfed back.

When the CRI=2, the bit meaning of the RI may mean that two RIs are fedback or an RI combination is fed back.

TABLE X34-1 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mapping RI forCRI = RI/RI combination o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) 0 or 1for CRI = 2 0, 0, 0, 0 1 {1, 1} 0, 0, 0, 1 2 {1, 2} 0, 0, 1, 0 3 {2, 1}0, 0, 1, 1 4 {2, 2} 0, 1, 0, 0 5 {2, 3} 0, 1, 0, 1 6 {3, 2} 0, 1, 1, 0 7{3, 3} 0, 1, 1, 1 8 {3, 4} 1, 0, 0, 0 Reserved {4, 3} 1, 0, 0, 1Reserved {4, 4} 1, 0, 1, 0 Reserved Reserved 1, 0, 1, 1 ReservedReserved 1, 1, 0, 0 Reserved Reserved 1, 1, 0, 1 Reserved Reserved 1, 1,1, 0 Reserved Reserved 1, 1, 1, 1 Reserved Reserved

Possible Manner 2:

The bit meaning of the RI is determined based on the first indicationinformation and at least one of the quantity of NZP CSI-RS resources,the quantity of antenna ports for an NZP CSI-RS, the capabilityinformation of the terminal device, the bit width of the RI, or thevalue of the CRI. In an example, the bit meaning of the RI may bedetermined based on the first indication information and the bit widthof the RI.

In one embodiment, the terminal may determine the bit meaning of the RIbased on the first indication information and the bit width of the RI.For example, when FeCoMPCSIEnabled is configured (or FeCoMPCSIEnabledand the aperiodic reporting mode are configured), when the bit width ofthe RI is 4, a bit meaning of RI (or RI combination) feedback mayinclude at least one item in Table 5.2.2.6-8-3:

TABLE 5.2.2.6-8-3 o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) to RI mappingo₀ ^(RI), o₁ ^(RI), o₂ ^(RI), o₃ ^(RI) RI/RI combination 0, 0, 0, 0 1 0,0, 0, 1 2 0, 0, 1, 0 3 0, 0, 1, 1 4 0, 1, 0, 0 5 or reserved 0, 1, 0, 16 or reserved 0, 1, 1, 0 {1, 1} 0, 1, 1, 1 {1, 2} 1, 0, 0, 0 {2, 1} 1,0, 0, 1 {2, 2} 1, 0, 1, 0 {2, 3} 1, 0, 1, 1 {3, 2} 1, 1, 0, 0 {3, 3} 1,1, 0, 1 {3, 4} 1, 1, 1, 0 {4, 3} 1, 1, 1, 1 {4, 4}

In one embodiment, the terminal may determine the bit meaning of the RIbased on the bit width of the RI.

For example, when determining that the bit width of the RI is 4, theterminal may determine that the bit meaning of the RI is at least oneitem in Table 5.2.2.6-8-3 above. It may be understood that, when the bitwidth of the RI is determined as 4, the foregoing bit meaning of the RIis also applicable without considering another factor such as the valueof the CRI.

In this embodiment of the present disclosure, a correspondence between avalue of at least one of the bits o₀ ^(RI), o₁ ^(RI), o₂ ^(RI), and o₃^(RI) and the value of the RI is merely an example, and anothercorrespondence is also applicable. This is not specifically limitedherein.

Possible Manner 2: When the RI and the CRI are jointly fed back orjointly encoded, the bit width of the RI is enabled to be independent ofthe value of the CRI, to be specific, it can be ensured that the bitwidth of the CRI and the bit width of the RI are known by both thenetwork device and the terminal device, so that the network device cancorrectly receive or decode the CRI and the RI. In addition, because thebit width of the RI is related to the quantity of antenna ports and/orthe capability of the terminal device, overheads for the bit width ofthe RI are relatively low.

In the solution described above, if there are a plurality of CSI-RSresources, a maximum value of quantities of antenna ports correspondingto these resources is used as a determined quantity of antenna ports forthe RI. Another method for determining the quantity of antenna ports forthe RI is described below. This embodiment may be used as an independentembodiment, or may be combined with another embodiment. This is notspecifically limited herein. It may be understood that a more detaileddetermining method is described below:

For coordinated multipoint transmission/reception mode (or FeCoMP orhybrid transmission mode or non-coherent transmission mode)-based CSImeasurement and/or feedback, the bit width of the RI is determined basedon a quantity of antenna ports for each CSI-RS resource.

In one embodiment, when a quantity of antenna ports for one CSI-RSresource is 1, and a quantity of antenna ports for another CSI-RSresource is M, the bit width of the RI may be 1 or ┌log₂ M┐. Whether aspecific bit width of the RI is 1 or ┌log₂ M┐ may be predefined in aprotocol, or notified by the base station by using signaling. This isnot specifically limited herein.

For example, there are two CSI-RS resources, a quantity of antenna portsfor one CSI-RS resource is 1, and a quantity of antenna ports for theother CSI-RS resource is M, where M is greater than 1. In this case, thebit width of the RI may be 1 or ┌log₂M┐.

When the bit width of the RI is 1, the 1 bit may be used to respectivelyindicate two values of the RI (or an RI combination) when the CRI=0, 1,or 2. For example, the RI=1 or 2 when the CRI=0 or 1 and the RI={1, 1}or {1, 2} when the CRI=2 are supported.

When the bit width of the RI is ┌log₂M┐, the ┌log₂ M┐ bits may be usedto respectively indicate M values of the RI (or an RI combination) whenthe CRI=0, 1, or 2. For example, the RI=1, 2, . . . , or M when theCRI=0 is supported, the RI=1, 2, . . . , or M when the CRI=1 issupported, and the RI={1, 1}, {1, 2}, . . . , or {1, M} when the CRI=2is supported.

In one embodiment, when a quantity of antenna ports for one CSI-RSresource is M1, and a quantity of antenna ports for at least one CSI-RSresource is M2, the bit width of the RI may be a maximum bit width ofthe RI in consideration of various values of the CRI.

Specifically, the terminal and/or the base station may determine themaximum bit width of the RI in the case of various values of the CRIbased on a bit width of the RI that corresponds to each CSI-RS resource,and then determine the bit width of the RI that is fed back.

For example, there are two CSI-RS resources, a quantity of antenna portsfor one CSI-RS resource is 2, and a quantity of antenna ports for theother CSI-RS resource is 4. In this case, the bit width of the RI may be2 or 3, which meets the maximum bit width of the RI in the case ofvarious values of the CRI. Whether a specific bit width of the RI is 2or 3 may be predefined in a protocol, or notified by the base station byusing signaling. This is not specifically limited herein.

A case in which the bit width of the RI is 2:

When a quantity of antenna ports for the first CSI-RS resource is 2, andCSI corresponding to the first CSI-RS resource is fed back (for example,the CRI=0), a corresponding RI needs to be fed back by using 1 bit, andthe 1 bit may be used to indicate that the RI=1 or 2. An example inwhich a quantity of antenna ports for the second CSI-RS resource is 4 isused. When CSI corresponding to the second CSI-RS resource is fed back(for example, the CRI=1), a corresponding RI needs to be fed back byusing 2 bits, and the 2 bits may be used to indicate that the RI=1, 2,3, or 4. When CSI corresponding to the first CSI-RS resource and CSIcorresponding to the second CSI-RS resource are fed back (for example,the CRI=2), corresponding RIs need to be fed back by using 2 bits, andthe 2 bits may be used to indicate that the RIs={1, 1}, {1, 2}, {2, 1},or {2, 3}. Therefore, in consideration of the maximum bit width of theRI in the case of various values of the CRI, it may be determined thatthe bit width for RI feedback is 2 bits. For example, the RI=1 or 2 whenthe CRI=0, the RI=1, 2, 3, or 4 when the CRI=1, and {1, 1}, {1, 2}, {2,1}, or {2, 3} when the CRI=2 are supported.

A case in which the bit width of the RI is 3:

When a quantity of antenna ports for the first CSI-RS resource is 2, andCSI corresponding to the first CSI-RS resource is fed back (for example,the CRI=0), a corresponding RI needs to be fed back by using 1 bit, andthe 1 bit may be used to indicate that the RI=1 or 2. An example inwhich a quantity of antenna ports for the second CSI-RS resource is 4 isused. When CSI corresponding to the second CSI-RS resource is fed back(for example, the CRI=1), a corresponding RI needs to be fed back byusing 2 bits, and the 2 bits may be used to indicate that the RI=1, 2,3, or 4. When CSI corresponding to the first CSI-RS resource and CSIcorresponding to the second CSI-RS resource are fed back (for example,the CRI=2), corresponding RIs need to be fed back by using 3 bits, andthe 3 bits may be used to indicate that the RIs={1, 1}, {1, 2}, {2, 1},{2, 3}, {1, 3}, {1, 4}, or {2, 4}. Therefore, in consideration of themaximum bit width of the RI in the case of various values of the CRI, itmay be determined that the bit width for RI feedback that is 3 bits canbe supported. For example, the RI=1 or 2 when the CRI=0, the RI=1, 2, 3,or 4 when the CRI=1, and {1, 1}, {1, 2}, {2, 1}, {2, 3}, {1, 3}, {1, 4},or {2, 4} when the CRI=2 are supported.

In one embodiment, in this embodiment of the present disclosure, unlessotherwise specified, a resource, a CRI-RS resource, and an NZP CSI-RSresource all refer to an NZP CSI-RS resource. Any description related toa quantity of antenna ports such as a quantity of antenna ports, aquantity of antenna ports for an NZP CSI-RS, or a quantity of antennaports for a CSI-RS resource refers to a quantity of antenna ports for anNZP CSI-RS resource.

The solution of determining CSI measurement and feedback is describedabove. The CSI may include at least one of a PMI, an RI, or a CQI, sothat reporting of the CSI is related to reporting of at least one of thePMI, the RI, or the CQI. In this case, there is a reporting sequence ofat least one of the PMI, the RI, or the CQI during reporting. Thefollowing describes an embodiment of a reporting sequence of the PMI andthe CQI and a method for determining a bit width of content included inthe CSI, for example, the PMI or the CQI. Methods for determining thereporting sequence and the bit width of the content included in the CSIin this embodiment may be independently implemented, or may be appliedin combination, or may be separately combined with other embodiments inthe present disclosure. This is not specifically limited herein.

In one embodiment, in this embodiment of the present disclosure, a firstset may be the CSI corresponding to the first NZP CSI-RS resource, and asecond set may be the CSI corresponding to the second NZP CSI-RSresource.

In one embodiment, in this embodiment of the present disclosure, a firstset may be CSI corresponding to the first codeword (for example, thecodeword 0), and a second set may be CSI corresponding to the secondcodeword (for example, a codeword 1).

In one embodiment, in this embodiment of the present disclosure, thefirst set, the first set, the first CSI set, the first set, and thefirst CSI set may have a same meaning, and may be replaced with eachother. In addition, the first set may be replaced with the CSI for thefirst codeword (for example, the codeword 0), the CSI corresponding tothe first NZP CSI-RS resource, or the like. This is not specificallylimited herein.

In one embodiment, in this embodiment of the present disclosure, thesecond set, the second set, the second CSI set, the second set, and thesecond CSI set may have a same meaning, and may be replaced with eachother. In addition, the second set may be replaced with the CSI for thesecond codeword (for example, the codeword 1), the CSI corresponding tothe second NZP CSI-RS resource, or the like. This is not specificallylimited herein.

There may be different reporting sequences (in this embodiment of thepresent disclosure, the reporting sequence may also be referred to as afeedback sequence) of PMIs and CQIs in a first set and a second set inone CSI process (or CSI reporting). For example, the terminal devicedetermines, based on the first indication information, to feed back atleast two CSI sets, where the at least two CSI sets include a first setof CSI and a second set of CSI, the first set of CSI includes a CQI ofthe first set and/or a PMI of the first set, and the second set of CSIincludes a CQI of the second set and/or a PMI of the second set.Reporting method 1: A CQI (including the CQI of the first set and/or theCQI of the second set) is first reported, and then a PMI (including thePMI of the first set and/or the PMI of the second set) is reported. Themethod 1 further includes at least one of the following several methods:

Method 1.1: If the first set includes only the CQI, and the second setalso includes only the CQI, the CQI of the first set and the CQI of thesecond set are sequentially reported.

Method 1.2: If the first set includes the CQI and the PMI, and thesecond set includes only the CQI, the CQI of the first set, the CQI ofthe second set, and the PMI of the first set are sequentially reported.

Method 1.3: If the first set includes the CQI and the PMI, and thesecond set includes the CQI and the PMI, the CQI of the first set, theCQI of the second set, the PMI of the first set, and the PMI of thesecond set are sequentially reported.

Method 1.4: If PMIs of each set include a first PMI and a second PMI,the first PMI (including the first PMI of the first set and/or the firstPMI of the second set) is first reported, and then the second PMI(including the second PMI of the first set and/or the second PMI of thesecond set) is reported.

Method 1.5: If PMIs of each set include a first PMI and a second PMI,the first PMI and/or the second PMI of the first set are/is firstreported, and then the first PMI and/or the second PMI of the second setare/is reported.

An example is used for description for the aperiodic reporting mode.

PMI feedback type Plurality of No Single (Multiple) PMI PMI PMIsPhysical Wideband Mode 1-0 Mode 1-1 Mode 1-2 uplink (wideband CQI)shared UE selected Mode 2-0 Mode 2-2 channel (subband CQI) (PUSCH) CQIHigher layer- Mode 3-0 Mode 3-1 Mode 3-2 Feedback configured Type(subband CQI)

For example, in a wideband CQI reporting mode, if no PMI is fed back, acorresponding mode is the mode 1-0.

A specific mode to be used may be predefined in a protocol, or may bedetermined through interaction between a base station and the terminal,for example, notified by the base station to the terminal by usingsignaling.

The following describes cases in the three reporting modes for Reportingmethod 1. The three reporting modes are: the wideband CQI reportingmode, the higher layer-configured subband CQI reporting mode, and the UEselected subband CQI reporting mode. In one embodiment, at least one ofthe following methods may be used for at least one of the threereporting mode.

Specifically, the reporting mode in this embodiment of the presentdisclosure may alternatively be a reporting mode in NR, 5G, or a futureresearch system. This is not specifically limited herein.

In one embodiment, the table in this embodiment of the presentdisclosure is used to determine a bit width of CSI feedback content, forexample, may be a bit width for CQI and/or PMI feedback.

In one embodiment, a sequence of the PMI and/or the CQI in the table mayalso be a reporting sequence of the CSI. For example, the terminal mayperform feedback from top to bottom based on the bit width indicated inthe table. Alternatively, the base station may determine informationindicated by the received CSI based on a sequence of the bit quantitiesindicated in the table. Specifically, a correspondence between asequence and a reporting sequence in the table may be predefined in aprotocol, or preconfigured on the base station and/or the terminal. Thisis not limited herein.

A. Wideband CQI Reporting Mode:

For wideband CQI reporting, when two CSI sets need to be reported, anexample of a reporting sequence in which a CQI (including a CQI of thefirst set and/or a CQI of the second set) is first reported and then aPMI (including a PMI of the first set and/or a PMI of the second set) isreported is used below for description. Specifically, at least one ofthe following manners may be used: (A1) For the mode 1-2, the reportingmanner may include at least one item in all tables shown in (A1).

In one embodiment, the mode 1-2 in the wideband CQI reporting mode maybe a feedback mode of a wideband CQI and a subband PMI.

For example, the following Table 5.2.2.6.1-1L-1 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode1-2 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. At least one of Table 5.2.2.6.1-1L-2-1 and Table5.2.2.6.1-1L-2-2 may be used to indicate a bit width for CSI feedbackand/or a CSI feedback sequence in the mode 1-2 when the first indicationinformation is configured and when the quantity of antenna ports is 8.At least one of Table 5.2.2.6.1-1L-3-1 and Table 5.2.2.6.1-1L-3-2 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 1-2 when the first indication information isconfigured and when the quantity of antenna ports is 4 and R12 codebookenhancement is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.1-1L-1 Scenarios for channel quality information feedbackfor wideband CQI and subband PMI reporting (Fields for channel qualityinformation feedback for wideband CQI and subband PMI reports) (thetransmission mode 10 is configured with PMI/RI reporting and the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’configured with two or four antenna ports with K > 1 CSI-RS resourcesand configured with the higher layer parameter FeCoMPCSIEnabled exceptwith configured R12 codebook enhancement) 2 antenna ports 4 antennaports Rank = Rank = Rank = Rank > Field 1 2 1 1 Bit width for CRI = 0 or1 Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 0 4Precoding matrix indicator   2N N   4N   4N Bit width for CRI = 2Wideband CQI of first CSI set 4 4 4 4 Wideband CQI of second CSI set 4 44 4 Precoding matrix indicator   2N N   4N   4N of first CSI setPrecoding matrix indicator   2N N   4N   4N of second CSI set

In the part “a bit width and/or a reporting sequence of content includedin the CSI”, N in the table is a quantity of subbands. Meanings in thefollowing tables are similar to this, and details are not describedagain.

Through the foregoing table, the terminal may determine, based on thequantity of antenna ports, the value of the CRI, and a rank value, a bitwidth for CQI and/or PMI feedback, for example, a bit width of awideband CQI corresponding to the codeword 0, a bit width of a widebandCQI corresponding to the codeword 1, and a bit width of the PMI when theCRI=0 or 1, for example, a bit width of a wideband CQI corresponding tothe first CSI set, a bit width of a wideband CQI corresponding to thesecond CSI set, a bit width of a PMI corresponding to the first CSI set,and a bit width of a PMI corresponding to the second CSI set when theCRI=2.

In one embodiment, the terminal may determine the CSI feedback sequencebased on content of the CSI in the table. For example, through theforegoing table, when the CRI=2, a feedback sequence of the two CSI setsis: a wideband CQI of the first set, a wideband CQI of the second set,the PMI of the first set, and the PMI of the second set. Explanations inother tables are similar to this, and details are not described again.

TABLE 5.2.2.6.1-1L-2-1 Scenarios for channel quality informationfeedback for wideband CQI and subband PMI reporting (Fields for channelquality information feedback for wideband CQI and subband PMI reports)(the transmission mode 10 is configured with PMI/RI reporting and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ configured with eight antenna ports with K > 1 CSI-RS resources andconfigured with the higher layer parameter FeCoMPCSIEnabled) Bit widthfor CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQIcodeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 4 4 Wideband first PMI i14 4 2 2 Subband second PMI i2   4N   4N   4N   3N Bit width for CRI = 0or 1 Rank = Rank = Rank = Rank = Field 5 6 7 8 Wideband CQI codeword 0 44 4 4 Wideband CQI codeword 1 4 4 4 4 Wideband first PMI i1 2 2 2 0Subband second PMI i2 0 0 0 0 Bit width for CRI = 2 Rank = Rank = Rank =Rank = Field 1 2 3 4 Wideband CQI of first set 4 4 4 4 Wideband CQI ofsecond set 4 4 4 4 Wideband first PMI i1 of 4 4 2 2 first set Widebandfirst PMI i1 of 4 4 2 2 second set Subband second PMI i2 of   4N   4N  4N   3N first set Subband second PMI i2 of   4N   4N   4N   3N secondset

The PMI it is the first PMI described above, and the PMI i2 is thesecond PMI described above. Meanings in the following tables are similarto this, and details are not described again.

Alternatively, Table 5.2.2.6.1-1L-2-1 may be replaced with the followingTable 5.2.2.6.1-1L-2-2:

Bit width for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 4 4 Widebandfirst PMI i1 4 4 2 2 Subband second PMI i2   4N   4N   4N   3N Bit widthfor CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 5 6 7 8 Wideband CQIcodeword 0 4 4 4 4 Wideband CQI codeword 1 4 4 4 4 Wideband first PMI i12 2 2 0 Subband second PMI i2 0 0 0 0 Bit width for CRI = 2 Rank = Rank= Rank = Rank = 1 2 3 4 Wideband CQI of first set 4 4 4 4 Wideband CQIof second set 4 4 4 4 Wideband first PMI i1 4 4 2 2 of first set Subbandsecond PMI i2   4N   4N   4N   3N of first set Wideband first PMI i1 4 42 2 of second set Subband second PMI i2   4N   4N   4N   3N of secondset

A difference between Table 5.2.2.6.1-1L-2-1 and Table 5.2.2.6.1-1L-2-2lies in that, in Table 5.2.2.6.1-1L-2-1, the first PMI of the first setand the first PMI of the second set are first reported, and then thesecond PMI of the first set and the second PMI of the second set arereported, while in Table 5.2.2.6.1-1L-2-2, the first PMI and the secondPMI of the first set are first reported, and then the first PMI and thesecond PMI of the second set are reported.

TABLE 5.2.2.6.1-1L-3-1 Scenarios for channel quality informationfeedback for wideband CQI and subband PMI reporting with four antennaports (Fields for channel quality information feedback for wideband CQIand subband PMI reports with 4 antenna ports) (the transmission mode 10is configured with PMI/RI reporting and the higher layer parametereMIMO-Type, eMIMO-Type is set to the ‘CLASS B’ configured with fourantenna ports with K > 1 CSI-RS resources and configured with the higherlayer parameter FeCoMPCSIEnabled with configured R12 codebookenhancement) Rank = Rank = Rank = Rank = Field 1 2 3 4 Bit width for CRI= 0 or 1 Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 4 4Wideband first PMI i1 4 4 0 0 Subband second PMI i2   4N   4N   4N   4NBit width for CRI = 2 Wideband CQI of first set 4 4 4 4 Wideband CQI ofsecond set 4 4 4 4 Wideband first PMI i1 of 4 4 0 0 first set Widebandfirst PMI i1 of 4 4 0 0 second set Subband second PMI i2 of   4N   4N  4N   4N first set Subband second PMI i2 of   4N   4N   4N   4N secondset

Alternatively, Table 5.2.2.6.1-1L-3-1 may be replaced with the followingTable 5.2.2.6.1-1L-3-2:

Rank = Rank = Rank = Rank = Field 1 2 3 4 Bit width for CRI = 0 or 1Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 4 4 Widebandfirst PMI i1 4 4 0 0 Subband second PMI i2   4N   4N   4N   4N Bit widthfor CRI = 2 Wideband CQI of first set 4 4 4 4 Wideband CQI of second set4 4 4 4 Wideband first PMI i1 of 4 4 0 0 first set Subband second PMI i2of   4N   4N   4N   4N first set Wideband first PMI i1 of 4 4 0 0 secondset Subband second PMI i2 of   4N   4N   4N   4N second set

A difference between Table 5.2.2.6.1-1L-3-1 and Table 5.2.2.6.1-1L-3-2lies in that, in Table 5.2.2.6.1-1L-3-1-1, the first PMI of the firstset and the first PMI of the second set are first reported, and then thesecond PMI of the first set and the second PMI of the second set arereported, while in Table 5.2.2.6.1-1L-3-2, the first PMI and the secondPMI of the first set are first reported, and then the first PMI and thesecond PMI of the second set are reported.

(A2) For the mode 1-0, the reporting manner may include at least oneitem in Table 5.2.2.6.1-1L-6 and Table 5.2.2.6.1-1L-7.

In one embodiment, the mode 1-0 in the wideband CQI reporting mode maybe a feedback mode of feedback of a wideband CQI and no feedback of aPMI.

For example, the following Table 5.2.2.6.1-1L-6 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode1-0 when the first indication information is configured and when thequantity of antenna ports is 1. Table 5.2.2.6.1-1L-7 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 1-0 when with the first indication information is configuredand when the quantity of antenna ports is 2/4/8 and no PMI feedback isconfigured. CSI feedback in another configuration is also applicable.This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.1-1L-6 Scenarios for channel quality information feedbackfor wideband CQI reporting (Fields for channel quality informationfeedback for wideband CQI reports) (the transmission mode 10 isconfigured without PMI/RI reporting or configured with one antenna portand configured with the higher layer parameter FeCoMPCSIEnabled) FieldBit width for CRI = 0 or 1 Wide-band CQI 4 Bit width for CRI = 2Wide-band CQI of first set 4 Wide-band CQI of second set 4

TABLE 5.2.2.6.1-1L-7 Scenarios for channel quality information feedbackfor wideband CQI reporting (Fields for channel quality informationfeedback forwideband CQI reports) (the transmission mode 10 isconfigured without PMI reporting and configured with the higher layerparameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ configuredwith two/four/eight antenna ports and configured with the higher layerparameter FeCoMPCSIEnabled) Rank = Rank > Field 1 1 Bit width for CRI =0 or 1 Wide-band CQI codeword 0 4 4 Wide-band CQI codeword 1 0 4 Bitwidth for CRI = 2 Wide-band CQI of first set 4 4 Wide-band CQI of secondset 4 4

(A3) For the mode 1-1, the reporting manner may include at least oneitem in all tables shown in (A3).

In one embodiment, the mode 1-1 in the wideband CQI reporting mode maybe a feedback mode of a wideband CQI and a wideband PMI.

For example, the following Table 5.2.2.6.1-1L-7 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode1-1 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. At least one of Table 5.2.2.6.1-1L-8-1 and Table5.2.2.6.1-1L-8-2 may be used to indicate a bit width for CSI feedbackand/or a CSI feedback sequence in the mode 1-1 when the first indicationinformation is configured and when the quantity of antenna ports is 8.At least one of Table 5.2.2.6.1-1L-9-1 and Table 5.2.2.6.1-1L-9-2 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 1-1 when the first indication information isconfigured and when the quantity of antenna ports is 4 and R12 codebookenhancement is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.1-1L-7 Scenarios for channel quality information feedbackfor wideband CQI reporting (Fields for channel quality informationfeedback for wideband CQI reports) (the transmission mode 10 isconfigured with PMI/RI reporting with two/four antenna ports and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ with K > 1 and configured with the higher layer parameterFeCoMPCSIEnabled except with configured R12 codebook enhancement) 2antenna ports 4 antenna ports Rank = Rank = Rank = Rank > Field 1 2 1 1Bit width for CRI = 0 or 1 Wide-band CQI codeword 0 4 4 4 4 Wide-bandCQI codeword 1 0 4 0 4 Precoding matrix indicator 2 1 4 4 Bit width forCRI = 2 Wide-band CQI of first set 4 4 4 4 Wide-band CQI of second set 44 4 4 Precoding matrix indicator of 2 1 4 4 first set Precoding matrixindicator of 2 1 4 4 second set

TABLE 5.2.2.6.1-1L-8-1 Scenarios for channel quality informationfeedback for wideband CQI reporting (Fields for channel qualityinformation feedback for wideband CQI reports) (the transmission mode 10is configured with PMI/RI reporting with eight antenna ports and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ with K > 1 and configured with the higher layer parameterFeCoMPCSIEnabled) Bit width for CRI = 0 or 1 Rank = Rank = Rank = Rank =Field 1 2 3 4 Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 04 4 4 Wideband first PMI i1 4 4 2 2 Wideband second PMI i2 4 4 4 3 Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 5 6 7 8Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 4 4 4 4 Widebandfirst PMI i1 2 2 2 0 Wideband second PMI i2 0 0 0 0 Bit width for CRI =2 Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 44 4 4 Wideband CQI of second set 4 4 4 4 Wideband first PMI i1 of 4 4 22 first set Wideband second PMI i2 of 4 4 4 3 first set Wideband firstPMI i1 of 4 4 2 2 second set Wideband second PMI i2 of 4 4 4 3 secondset

Alternatively, Table 5.2.2.6.1-1L-8-1 may be replaced with the followingTable 5.2.2.6.1-1L-8-2:

Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 4 4 Widebandfirst PMI i1 4 4 2 2 Wideband second PMI i2 4 4 4 3 Bitwidth for CRI = 0or 1 Rank = Rank = Rank = Rank = Field 5 6 7 8 Wideband CQI codeword 0 44 4 4 Wideband CQI codeword 1 4 4 4 4 Wideband first PMI i1 2 2 2 0Wideband second PMI i2 0 0 0 0 Bitwidth for CRI = 2 Rank = Rank = Rank =Rank = Field 1 2 3 4 Wideband CQI of first set 4 4 4 4 Wideband CQI ofsecond set 4 4 4 4 Wideband first PMI i1 of 4 4 2 2 first set Widebandfirst PMI i1 of 4 4 2 2 second set Wideband second PMI i2 of 4 4 4 3first set Wideband second PMI i2 of 4 4 4 3 second set

A difference between Table 5.2.2.6.1-1L-8-1 and Table 5.2.2.6.1-1L-8-2lies in that, in Table 5.2.2.6.1-1L-8-1, the first PMI and the secondPMI of the first set are first reported, and then the first PMI and thesecond PMI of the second set are reported, while in Table5.2.2.6.1-1L-8-2, the first PMI of the first set and the first PMI ofthe second set are first reported, and then the second PMI of the firstset and the second PMI of the second set are reported.

TABLE 5.2.2.6.1-1L-9-1 Scenarios for channel quality informationfeedback for wideband CQI reporting with four antenna ports (Fields forchannel quality information feedback for wideband CQI reports with 4antenna ports) (the transmission mode 10 is configured with PMI/RIreporting with four antenna ports and the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with K > 1 andconfigured with the higher layer parameter FeCoMPCSIEnabled withconfigured R12 codebook enhancement) Rank = Rank = Rank = Rank = Field 12 3 4 Bitwidth for CRI = 0 or 1 Wideband CQI codeword 0 4 4 4 4 WidebandCQI codeword 1 0 4 4 4 Wideband first PMI i1 4 4 0 0 Wideband second PMIi2 4 4 4 4 Bitwidth for CRI = 2 Wideband CQI of first set 4 4 4 4Wideband CQI of second set 4 4 4 4 Wideband first PMI i1 of 4 4 0 0first set Wideband second PMI i2 of 4 4 4 4 first set Wideband first PMIi1 of 4 4 0 0 second set Wideband second PMI i2 of 4 4 4 4 second set

Alternatively, Table 5.2.2.6.1-1L-9-1 may be replaced with the followingTable 5.2.2.6.1-1L-9-2:

Rank = Rank = Rank = Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 0 4 4 4 Widebandfirst PMI i1 4 4 0 0 Wideband second PMI i2 4 4 4 4 Bitwidth for CRI = 2Wideband CQI of first set 4 4 4 4 Wideband CQI of second set 4 4 4 4Wideband first PMI i1 of 4 4 0 0 first set Wideband first PMI i1 of 4 40 0 second set Wideband second PMI i2 of 4 4 4 4 first set Widebandsecond PMI i2 of 4 4 4 4 second set

A difference between Table 5.2.2.6.1-1L-9-1 and Table 5.2.2.6.1-1L-9-2lies in that, in Table 5.2.2.6.1-1L-9-1, the first PMI and the secondPMI of the first set are first reported, and then the first PMI and thesecond PMI of the second set are reported, while in Table5.2.2.6.1-1L-9-2, the first PMI of the first set and the first PMI ofthe second set are first reported, and then the second PMI of the firstset and the second PMI of the second set are reported.

B. Higher Layer-Configured Subband CQI Reporting Mode:

For higher layer-configured subband CQI reporting, when two CSI setsneed to be reported, an example of a reporting sequence in which a CQI(including a CQI of the first set and/or a CQI of the second set) isfirst reported and then a PMI (including a PMI of the first set and/or aPMI of the second set) is reported is used below for description.Specifically, at least one of the following manners may be used: (B1)For the mode 3-0, the reporting manner may include at least one item inTable 5.2.2.6.2-1B-1 and Table 5.2.2.6.2-1B-2.

In one embodiment, the mode 3-0 in the higher layer-configured subbandCQI reporting mode may be a feedback mode of feedback of a higherlayer-configured subband CQI and no feedback of a PMI.

For example, the following Table 5.2.2.6.2-1B-1 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode3-0 when the first indication information is configured and when thequantity of antenna ports is 1. Table 5.2.2.6.2-1B-2 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 3-0 when the first indication information is configured andwhen the quantity of antenna ports is 2/4/8 and no PMI feedback isconfigured. CSI feedback in another configuration is also applicable.This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter. CSIfeedback in another configuration is also applicable. This is notspecifically limited herein.

TABLE 5.2.2.6.2-1B-1 Scenarios for channel quality information feedbackfor higher layer-configured subband CQI reporting (Fields for channelquality information feedback for higher layer configured subband CQIreports) (the transmission mode 10 is configured with PMI/RI reportingor configured with one antenna port and configured with the higher layerparameter FeCoMPCSIEnabled) Field Bit width for CRI = 0 or 1 Wide-bandCQI codeword 4 Subband differential CQI   2N Bit width for CRI = 2Wide-band CQI of first set 4 Subband differential CQI   2N of first setWide-band CQI of second set 4 Subband differential CQI   2N of secondset

TABLE 5.2.2.6.2-1B-2 Scenarios for channel quality information feedbackfor higher layer-configured subband CQI reporting (Fields for channelquality information feedback for higher layer configured subband CQIreports) (the transmission mode 10 is configured without PMI reportingand configured with the higher layer parameter eMIMO-Type, andeMIMO-Type is set to the ‘CLASS B’ configured with two/four/eightantenna ports and configured with the higher layer parameterFeCoMPCSIEnabled) Field Rank = 1 Rank > 1 Bit width for CRI = 0 or 1Wide-band CQI codeword 0 4 4 Subband differential CQI codeword 0   2N  2N Wide-band CQI codeword 1 0 4 Subband differential CQI codeword 1 0  2N Bit width for CRI = 2 Wide-band CQI of first set 4 4 Subbanddifferential CQI of first set   2N   2N Wide-band CQI of second set 4 4Subband differential CQI of second set   2N   2N

(B2) For the mode 3-1, the reporting manner may include at least oneitem in all tables shown in (B2).

In one embodiment, the mode 3-1 in the higher layer-configured subbandCQI reporting mode may be a feedback mode of a higher layer-configuredsubband CQI and a wideband PMI.

For example, the following Table 5.2.2.6.2-2F-1 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode3-1 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. At least one of Table 5.2.2.6.2-2F-2-1 and Table5.2.2.6.2-2F-2-2 may be used to indicate a bit width for CSI feedbackand/or a CSI feedback sequence in the mode 3-1 when the first indicationinformation is configured and when the quantity of antenna ports is 8.At least one of Table 5.2.2.6.2-2F-3-1 and Table 5.2.2.6.2-2F-3-2 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 3-1 when the first indication information isconfigured and when the quantity of antenna ports is 4 and R12 codebookenhancement is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.2-2F-1 Scenarios for channel quality information feedbackfor higher layer-configured subband CQI reporting (Fields for channelquality information feedback for higher layer configured subband CQIreports) (the transmission mode 10 is configured with PMI/RI reportingwith two/four antenna ports and the higher layer parameter eMIMO-Type,and eMIMO-Type is set to the ‘CLASS B’ with K > 1 and configured withthe higher layer parameter FeCoMPCSIEnabled except with configured R12codebook enhancement) 2 antenna ports 4 antenna ports Rank = Rank = Rank= Rank > Field 1 2 1 1 Bit width for CRI = 0 or 1 Wide-band CQI codeword0 4 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword 0Wide-band CQI codeword 1 0 4 0 4 Subband differential CQI 0   2N 0   2Ncodeword 1 Precoding matrix indicator 2 1 4 4 Bit width for CRI = 2Wide-band CQI of first set 4 4 4 4 Subband differential CQI of   2N   2N  2N   2N first set Wide-band CQI of second set 4 4 0 4 Subbanddifferential CQI of   2N   2N 0   2N second set Precoding matrixindicator of 2 1 4 4 first set Precoding matrix indicator of 2 1 4 4second set

TABLE 5.2.2.6.2-2F-2-1 Scenarios for channel quality informationfeedback for higher layer- configured subband CQI reporting (Fields forchannel quality information feedback for higher layer configured subbandCQI reports) (the transmission mode 10 is configured with PMI/RIreporting with eight antenna ports and the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with K > 1 andconfigured with the higher layer parameter FeCoMPCSIEnabled) Bitwidthfor CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQIcodeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI 0   2N   2N  2N codeword 1 Wideband first PMI i1 4 4 2 2 Wideband second PMI i2 4 44 3 Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 5 6 7 8Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 4 4 4 4 Subband differential CQI  2N   2N   2N   2N codeword 1 Wideband first PMI i1 2 2 2 0 Widebandsecond PMI i2 0 0 0 0 Bitwidth for CRI = 2 Rank = Rank = Rank = Rank =Field 1 2 3 4 Wideband CQI of first set 4 4 4 4 Subband differential CQI  2N   2N   2N   2N of first set Wideband CQI of second set 0 4 4 4Subband differential CQI 0   2N   2N   2N of second set Wideband firstPMI i1 of 4 4 2 2 first set Wideband first PMI i1 of 4 4 2 2 second setWideband second PMI i2 of 4 4 4 3 first set Wideband second PMI i2 of 44 4 3 second set

Alternatively, Table 5.2.2.6.2-2F-2-1 may be replaced with the followingTable 5.2.2.6.2-2F-2-2:

Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 2 2 Widebandsecond PMI i2 4 4 4 3 Bitwidth for CRI = 0 or 1 Rank = Rank = Rank =Rank = Field 5 6 7 8 Wideband CQI codeword 0 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N codeword 0 Wideband CQI codeword 14 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword 1 Widebandfirst PMI i1 2 2 2 0 Wideband second PMI i2 0 0 0 0 Bitwidth for CRI = 2Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 4 44 4 Subband differential CQI of   2N   2N   2N   2N first set WidebandCQI of second set 0 4 4 4 Subband differential CQI of 0   2N   2N   2Nsecond set Wideband first PMI i1 of 4 4 2 2 first set Wideband secondPMI i2 of 4 4 4 3 first set Wideband first PMI i1 of 4 4 2 2 second setWideband second PMI i2 of 4 4 4 3 second set

TABLE 5.2.2.6.2-2F-3-1 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI reporting with fourantenna ports (Fields for channel quality information feedback forhigher layer configured subband CQI reports with 4 antenna ports) (thetransmission mode 10 is configured with PMI/RI reporting with fourantenna ports and the higher layer parameter eMIMO- Type, and eMIMO-Typeis set to the ‘CLASS B’ with K > 1 and configured with the higher layerparameter FeCoMPCSIEnabled with configured R12 codebook enhancement)Rank = Rank = Rank = Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 0 0 Widebandsecond PMI i2 4 4 4 4 Bitwidth for CRI = 2 Wideband CQI of first set 4 44 4 Subband differential CQI   2N   2N   2N   2N of first set WidebandCQI of second set 4 4 4 4 Subband differential CQI   2N   2N   2N   2Nof second set Wideband first PMI i1 of 4 4 0 0 first set Wideband firstPMI i1 of 4 4 0 0 second set Wideband second PMI i2 of 4 4 4 4 first setWideband second PMI i2 of 4 4 4 4 second set

Alternatively, Table 5.2.2.6.2-2F-3-1 may be replaced with the followingTable 5.2.2.6.2-2F-3-2:

Rank = Rank = Rank = Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 0 0 Widebandsecond PMI i2 4 4 4 4 Bitwidth for CRI = 2 Wideband CQI of first set 4 44 4 Subband differential CQI of   2N   2N   2N   2N first set WidebandCQI of second set 4 4 4 4 Subband differential CQI of   2N   2N   2N  2N second set Wideband first PMI i1 of 4 4 0 0 first set Widebandsecond PMI i2 of 4 4 4 4 first set Wideband first PMI i1 of 4 4 0 0second set Wideband second PMI i2 of 4 4 4 4 second set

A difference between Table 5.2.2.6.2-2F-3-2 and Table 5.2.2.6.2-2F-3-1lies in that, in Table 5.2.2.6.2-2F-3-2, the first PMI and the secondPMI of the first set are first reported, and then the first PMI and thesecond PMI of the second set are reported, while in Table5.2.2.6.2-2F-3-1, the first PMI of the first set and the first PMI ofthe second set are first reported, and then the second PMI of the firstset and the second PMI of the second set are reported.

(B3) For the mode 3-2, the reporting manner may include at least oneitem in all tables shown in (B3).

In one embodiment, the mode 3-2 in the higher layer-configured subbandCQI reporting mode may be a feedback mode of a higher layer-configuredsubband CQI and a subband PMI.

For example, the following Table 5.2.2.6.2-2G may be used to indicate abit width for CSI feedback and/or a CSI feedback sequence in the mode3-2 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. At least one of Table 5.2.2.6.2-2G-1-1 and Table5.2.2.6.2-2G-1-2 may be used to indicate a bit width for CSI feedbackand/or a CSI feedback sequence in the mode 3-2 when the first indicationinformation is configured and when the quantity of antenna ports is 8.At least one of Table 5.2.2.6.2-2G-2-1 and Table 5.2.2.6.2-2G-2-2 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 3-2 when the first indication information isconfigured and when the quantity of antenna ports is 4 and R12 codebookenhancement is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.2-2G Scenarios for channel quality information feedbackfor higher layer-configured subband CQI and subband PMI reporting(Fields for channel quality information feedback for higher layerconfigured subband CQI and subband PMI reports) (the transmission mode10 is configured with subband PMI/RI reporting with two/four antennaports and configured with the higher layer parameter eMIMO-Type, andeMIMO-Type is set to the ‘CLASS B’ with K > 1 and configured with thehigher layer parameter FeCoMPCSIEnabled except with configured R12codebook enhancement) 2 antenna ports 4 antenna ports Rank = Rank = Rank= Rank = Rank = Rank = Field 1 2 1 2 3 4 Bit width for CRI = 0 or 1Wide-band 4 4 4 4   4   4   CQI codeword 0 Subband   2N   2N   2N 2N 2N2N differential CQI codeword 0 Wide-band 0 4 0 4   4   4   CQI codeword1 Subband 0   2N 0 2N 2N 2N differential CQI codeword 1 Subband   2N N  4N 4N 4N 4N precoding matrix indicator Bit width for CRI = 2 Wide-band4 4 4 4   4   4   CQI of first set Subband   2N   2N   2N 2N 2N 2Ndifferential CQI of first set Wide-band 4 4 4 4   4   4   CQI of secondset Subband   2N   2N   2N 2N 2N 2N differential CQI of second setSubband   2N N   4N 4N 4N 4N precoding matrix indicator of first setSubband   2N N   4N 4N 4N 4N precoding matrix indicator of second set

TABLE 5.2.2.6.2-2G-1-1 Scenarios for channel quality informationfeedback for higher layer- configured subband CQI and subband PMIreporting with eight antenna ports (Fields for channel qualityinformation feedback for higher layer configured subband CQI and subbandPMI reports with 8 antenna ports) (the transmission mode 10 isconfigured with subband PMI/RI reporting and configured with the higherlayer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ withK > 1 and configured with the higher layer parameter FeCoMPCSIEnabled)Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 2 2 Subband secondPMI i2   4N   4N   4N   3N Bitwidth for CRI = 0 or 1 Rank = Rank = Rank= Rank = Field 5 6 7 8 Wideband CQI codeword 0 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N codeword 0 Wideband CQI codeword 14 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword 1 Widebandfirst PMI i1 2 2 2 0 Subband second PMI i2 0 0 0 0 Bitwidth for CRI = 2Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 4 44 4 Subband differential CQI   2N   2N   2N   2N of first set WidebandCQI of second set 4 4 4 4 Subband differential CQI   2N   2N   2N   2Nof second set Wideband first PMI i1 of 4 4 2 2 first set Subband secondPMI i2 of   4N   4N   4N   3N first set Wideband first PMI i1 of 4 4 2 2second set Subband second PMI i2 of   4N   4N   4N   3N second set

Alternatively, Table 5.2.2.6.2-2G-1-1 may be replaced with the followingTable 5.2.2.6.2-2G-1-2:

Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 2 2 Subband secondPMI i2   4N   4N   4N   3N Bitwidth for CRI = 0 or 1 Rank = Rank = Rank= Rank = Field 5 6 7 8 Wideband CQI codeword 0 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N codeword 0 Wideband CQI codeword 14 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword 1 Widebandfirst PMI i1 2 2 2 0 Subband second PMI i2 0 0 0 0 Bitwidth for CRI = 2Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 4 44 4 Subband differential CQI   2N   2N   2N   2N of first set WidebandCQI of second set 4 4 4 4 Subband differential CQI   2N   2N   2N   2Nof second set Wideband first PMI i1 of 4 4 2 2 first set Wideband firstPMI i1 of 4 4 2 2 second set Subband second PMI i2 of   4N   4N   4N  3N first set Subband second PMI i2 of   4N   4N   4N   3N second set

TABLE 5.2.2.6.2-2G-2-1 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI and subband PMIreporting with four antenna ports (Fields for channel qualityinformation feedback for higher layer configured subband CQI and subbandPMI reports with 4 antenna ports) (the transmission mode 10 isconfigured with subband PMI/RI reporting with four antenna ports andconfigured with the higher layer parameter eMIMO-Type, and eMIMO-Type isset to the ‘CLASS B’ with K > 1 and configured with the higher layerparameter FeCoMPCSIEnabled with configured R12 codebook enhancement(transmission mode 10 configured with subband PMI/RI reporting with 4antenna ports and higher layer parameter eMIMO-Type, and eMIMO-Type isset to ‘CLASS B’ with K > 1 and higher layer parameter FeCoMPCSIEnabledwith alternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank = Rank = Rank =Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1 Wideband CQI codeword 0 44 4 4 Subband differential CQI   2N   2N   2N   2N codeword 0 WidebandCQI codeword 1 0 4 4 4 Subband differential CQI 0   2N   2N   2Ncodeword 1 Wideband first PMI i1 4 4 0 0 Subband second PMI i2   4N   4N  4N   4N Bitwidth for CRI = 2 Wideband CQI of first set 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N of first set Wideband CQI of secondset 4 4 4 4 Subband differential CQI   2N   2N   2N   2N of second setWideband first PMI i1 of 4 4 0 0 first set Subband second PMI i2 of   4N  4N   4N   4N first set Wideband first PMI i1 of 4 4 0 0 second setSubband second PMI i2 of   4N   4N   4N   4N second set

Alternatively, Table 5.2.2.6.2-2G-2-1 may be replaced with the followingTable 5.2.2.6.2-2G-2-2:

Rank = Rank = Rank = Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 0 0 Subband secondPMI i2   4N   4N   4N   4N Bitwidth for CRI = 2 Wideband CQI of firstset 4 4 4 4 Subband differential CQI   2N   2N   2N   2N of first setWideband CQI of second set 4 4 4 4 Subband differential CQI   2N   2N  2N   2N of second set Wideband first PMI i1 of 4 4 0 0 first setWideband first PMI i1 of 4 4 0 0 second set Subband second PMI i2 of  4N   4N   4N   4N first set Subband second PMI i2 of   4N   4N   4N  4N second set

C. UE Selected Subband CQI Reporting Mode

For UE selected subband CQI reporting, for example, if UE selects Msubbands, feedback of positions of the M selected subbands may befinally performed, that is, after all CQIs and/or PMIs are fed back inthe UE selected subband CQI reporting mode; or may be performed afterCQI feedback and before PMI feedback in the UE selected subband CQIreporting mode; or may be first performed for CSI in the UE selectedsubband CQI reporting mode, that is, performed before CQI and/or PMIfeedback in the UE selected subband CQI reporting mode. This is notspecifically limited.

In one embodiment, for the positions of the M selected subbands, onlyone reporting parameter may be fed back for two CSI sets, and theparameter is used to indicate the positions of the M selected subbands.Alternatively, each of the CSI sets may include one reporting parameter,and the reporting parameter is used to feed back the positions of the Mselected subbands. This is not specifically limited herein.

An example of a reporting sequence of reporting a CQI (including a CQIof the first set and a CQI of the second set), the positions of the Mselected subbands, and a PMI (including a PMI of the first set and a PMIof the second set) is used below for description.

(C1) For the mode 2-0, the reporting manner may include at least oneitem in Table 5.2.2.6.3-1B-1 and Table 5.2.2.6.3-1B-2.

In one embodiment, the mode 2-0 in the UE selected subband CQI reportingmode may be a feedback mode of feedback of a UE selected subband CQI andno feedback of a PMI.

For example, the following Table 5.2.2.6.3-1B-1 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode1-0 when the first indication information is configured and when thequantity of antenna ports is 1. Table 5.2.2.6.3-1B-2 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 1-0 when with the first indication information is configuredand when the quantity of antenna ports is 2/4/8 and no PMI feedback isconfigured. CSI feedback in another configuration is also applicable.This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.63-1B-1 Scenarios for channel quality information feedbackfor UE selected subband CQI reporting (Fields for channel qualityinformation feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting with oneantenna port and configured with the higher layer parameterFeCoMPCSIEnabled) Field Bit width for CRI = 0 or 1 Wide-band CQIcodeword 4 Subband differential CQI 2 Position of the M selectedsubbands L Bit width for CRI = 2 Wide-band CQI of first set 4 Subbanddifferential CQI of first set 2 Wide-band CQI of second set 4 Subbanddifferential CQI of second set 2 Position of the M selected subbands L

L indicates a quantity of bits occupied by feedback of the M subbands.Meanings in the following tables are similar to this, and details arenot described again.

TABLE 5.2.2.63-1B-2 Scenarios for channel quality information feedbackfor UE selected subband CQI reporting (Fields for channel qualityinformation feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured without PMI reporting and configuredwith the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ with two/four/eight antenna ports and configured with thehigher layer parameter FeCoMPCSIEnabled) Field Rank = 1 Rank > 1 Bitwidth for CRI = 0 or 1 Wide-band CQI codeword 0 4 4 Subband differentialCQI codeword 0 2 2 Wide-band CQI codeword 1 0 4 Subband differential CQIcodeword 1 0 2 Position of the M selected subbands L L Bit width for CRI= 2 Wide-band CQI of first set 4 4 Subband differential CQI of first set2 2 Wide-band CQI of second set 4 4 Subband differential CQI of secondset 2 2 Position of the M selected subbands L L

(C2) For the mode 2-2, the reporting manner may include at least oneitem in all tables shown in (C2).

In one embodiment, the mode 2-2 in the UE selected subband CQI reportingmode may be a feedback mode of a wideband CQI and a subband PMI.

For example, the following Table 5.2.2.6.3-2K may be used to indicate abit width for CSI feedback and/or a CSI feedback sequence in the mode2-2 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. At least one of Table 5.2.2.6.3-2K-1-1, Table5.2.2.6.3-2K-1-2, and Table 5.2.2.6.3-2K-1-3 may be used to indicate abit width for CSI feedback and/or a CSI feedback sequence in the mode2-2 when the first indication information is configured and when thequantity of antenna ports is 8. At least one of Table 5.2.2.6.3-2K-2-1,Table 5.2.2.6.3-2K-2-2, and Table 5.2.2.6.3-2K-2-3 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 2-2 when the first indication information is configured andwhen the quantity of antenna ports is 4 and R12 codebook enhancement isconfigured. CSI feedback in another configuration is also applicable.This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.3-2K Scenarios for channel quality information feedbackfor UE selected subband CQI reporting (Fields for channel qualityinformation feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting with two/fourantenna ports and configured with the higher layer parameter eMIMO-Type,and eMIMO-Type is set to ‘CLASS B’ with K > 1 and configured with thehigher layer parameter FeCoMPCSIEnabled except with configured R12codebook enhancement (transmission mode 10 configured with PMI/RIreporting with 2/4 antenna ports and higher layer parameter eMIMO-Type,and eMIMO-Type is set to ‘CLASS B’ with K > 1, and higher layerparameter FeCoMPCSIEnabled except withalternativeCodeBookEnabledFor4TX-r12 = TRUE)) 2 antenna ports 4 antennaports Rank = Rank = Rank = Rank > Field 1 2 1 1 Bit width for CRI = 0 or1 Wide-band CQI codeword 0 4 4 4 4 Subband differential CQI 2 2 2 2codeword 0 Wide-band CQI codeword 1 0 4 0 4 Subband differential CQI 0 20 2 codeword 1 Position of the M selected L L L L subbands Precodingmatrix indicator 4 2 8 8 Bit width for CRI = 2 Wide-band CQI of firstset 4 4 4 4 Subband differential CQI 2 2 2 2 of first set Wide-band CQIof second set 4 4 4 4 Subband differential CQI 2 2 2 2 of second setPosition of the M selected L L L L subbands Precoding matrix indicator 42 8 8 of first set Precoding matrix indicator 4 2 8 8 of second set

TABLE 5.2.2.6.3-2K-1-1 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting (Fields for channelquality information feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting with eightantenna ports and configured with the higher layer parameter eMIMO-Type,and eMIMO-Type is set to the ‘CLASS B’ with K > 1 and configured withthe higher layer parameter FeCoMPCSIEnabled) Rank = Rank = Rank = Rank =Rank = Rank = Rank = Rank = Field 1 2 3 4 5 6 7 8 Bit width for CRI = 0or 1 Wide-band 4 4 4 4 4 4 4 4 CQI codeword 0 Subband 2 2 2 2 2 2 2 2differential CQI codeword 0 Wide-band 0 4 4 4 4 4 4 4 CQI codeword 1Subband 0 2 2 2 2 2 2 2 differential CQI codeword 1 Bit width for CRI =0 or 1 Position of L L L L L L L L the M selected subbands Wideband 4 42 2 2 2 2 0 first PMI i1 Wideband 4 4 4 3 0 0 0 0 second PMI i2 Subband4 4 4 3 0 0 0 0 second PMI i2 Bit width for CRI = 2 Rank = Rank = Rank =Rank = Field 1 2 3 4 Wide-band CQI of first set 4 4 4 4 Subbanddifferential CQI of first set 2 2 2 2 Wide-band CQI of second set 4 4 44 Subband differential CQI of second set 2 2 2 2 Position of the Mselected subbands L L L L Wideband first PMI i1 of first set 4 4 2 2Wideband first PMI i1 of second set 4 4 2 2 Wideband second PMI i2 offirst set 4 4 4 3 Wideband second PMI i2 of second set 4 4 4 3 Subbandsecond PMI i2 of first set 4 4 4 3 Subband second PMI i2 of second set 44 4 3

Alternatively, Table 5.2.2.6.3-2K-1-1 may be replaced with the followingTable 5.2.2.6.3-2K-1-2:

Bit width for CRI = 0 or 1 Rank = Rank = Rank = Rank = Rank = Rank =Rank = Rank = Field 1 2 3 4 5 6 7 8 Wide-band 4 4 4 4 4 4 4 4 CQIcodeword 0 Subband 2 2 2 2 2 2 2 2 differential CQI codeword 0 Wide-band0 4 4 4 4 4 4 4 CQI codeword 1 Subband 0 2 2 2 2 2 2 2 differential CQIcodeword 1 Position of L L L L L L L L the M selected subbands Wideband4 4 2 2 2 2 2 0 first PMI i1 Wideband 4 4 4 3 0 0 0 0 second PMI i2Subband 4 4 4 3 0 0 0 0 second PMI i2 Bit width for CRI = 2 Rank = Rank= Rank = Rank = Field 1 2 3 4 Wide-band CQI of first set 4 4 4 4 Subbanddifferential CQI of first set 2 2 2 2 Wide-band CQI of second set 4 4 44 Subband differential CQI of second set 2 2 2 2 Position of the Mselected subbands L L L L Wideband first PMI i1 of first set 4 4 2 2Wideband second PMI i2 of first set 4 4 4 3 Subband second PMI i2 offirst set 4 4 4 3 Wideband first PMI i1 of second set 4 4 2 2 Widebandsecond PMI i2 of second set 4 4 4 3 Subband second PMI i2 of second set4 4 4 3

Alternatively, Table 5.2.2.6.3-2K-1-1 or Table 5.2.2.6.3-2K-1-2 may bereplaced with the following Table 5.2.2.6.3-2K-1-3:

Rank = Rank = Rank = Rank = Rank = Rank = Rank = Rank = Field 1 2 3 4 56 7 8 Bit width for CRI = 0 or 1 Wide-band 4 4 4 4 4 4 4 4 CQI codeword0 Subband 2 2 2 2 2 2 2 2 differential CQI codeword 0 Wide-band 0 4 4 44 4 4 4 CQI codeword 1 Subband 0 2 2 2 2 2 2 2 differential CQI codeword1 Bit width for CRI = 0 or 1 Position of L L L L L L L L the M selectedsubbands Wideband 4 4 2 2 2 2 2 0 first PMI i1 Wideband 4 4 4 3 0 0 0 0second PMI i2 Subband 4 4 4 3 0 0 0 0 second PMI i2 Bit width for CRI =2 Rank = Rank = Rank = Rank = Field 1 2 3 4 Wide-band CQI of first set 44 4 4 Subband differential CQI of first set 2 2 2 2 Wide-band CQI ofsecond set 4 4 4 4 Subband differential CQI of second set 2 2 2 2Position of the M selected subbands L L L L Wideband first PMI i1 offirst set 4 4 2 2 Wideband second PMI i2 of first set 4 4 4 3 Widebandfirst PMI i1 of second set 4 4 2 2 Wideband second PMI i2 of second set4 4 4 3 Subband second PMI i2 of first set 4 4 4 3 Subband second PMI i2of second set 4 4 4 3

TABLE 5.2.2.6.3-2K-2-1 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting with four antenna ports(Fields for channel quality information feedback for UE selected subbandCQI reports with 4 antenna ports) (the transmission mode 10 isconfigured with PMI/RI reporting with four antenna ports and configuredwith the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ with K > 1 and configured with the higher layer parameterFeCoMPCSIEnabled with configured R12 codebook enhancement (transmissionmode 10 configured with PMI/RI reporting with 4 antenna ports and higherlayer parameter eMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with K >1, and higher layer parameter FeCoMPCSIEnabled withalternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank = Rank = Rank = Rank= Field 1 2 3 4 Bit width for CRI = 0 or 1 Wide-band CQI codeword 0 4 44 4 Subband differential CQI 2 2 2 2 codeword 0 Wide-band CQI codeword 10 4 4 4 Subband differential CQI 0 2 2 2 codeword 1 Position of the Mselected L L L L subbands Wideband first PMI i1 4 4 0 0 Wideband secondPMI i2 4 4 4 4 Subband second PMI i2 4 4 4 4 Bit width for CRI = 2Wide-band CQI of first set 4 4 4 4 Subband differential CQI 2 2 2 2 offirst set Wide-band CQI of second set 4 4 4 4 Subband differential CQI 22 2 2 of second set Position of the M selected L L L L subbands Widebandfirst PMI i1 of 4 4 0 0 first set Wideband first PMI i1 of 4 4 0 0second set Wideband second PMI i2 of 4 4 4 4 first set Wideband secondPMI i2 of 4 4 4 4 second set Subband second PMI i2 of 4 4 4 4 first setSubband second PMI i2 of 4 4 4 4 second set

Alternatively, Table 5.2.2.6.3-2K-2-1 may be replaced with the followingTable 5.2.2.6.3-2K-2-2:

Rank = Rank = Rank = Rank = Field 1 2 3 4 Bit width for CRI = 0 or 1Wide-band CQI codeword 0 4 4 4 4 Subband differential CQI 2 2 2 2codeword 0 Wide-band CQI codeword 1 0 4 4 4 Subband differential CQI 0 22 2 codeword 1 Position of the M selected L L L L subbands Widebandfirst PMI i1 4 4 0 0 Wideband second PMI i2 4 4 4 4 Subband second PMIi2 4 4 4 4 Bit width for CRI = 2 Wide-band CQI of first set 4 4 4 4Subband differential CQI 2 2 2 2 of first set Wide-band CQI of secondset 4 4 4 4 Subband differential CQI 2 2 2 2 of second set Position ofthe M selected L L L L subbands Wideband first PMI i1 of 4 4 0 0 firstset Wideband second PMI i2 of 4 4 4 4 first set Subband second PMI i2 of4 4 4 4 first set Wideband first PMI i1 of 4 4 0 0 second set Widebandsecond PMI i2 of 4 4 4 4 second set Subband second PMI i2 of 4 4 4 4second set

Alternatively, Table 5.2.2.6.3-2K-2-1 or Table 5.2.2.6.3-2K-2-2 may bereplaced with the following Table 5.2.2.6.3-2K-2-3:

Rank = Rank = Rank = Rank = Field 1 2 3 4 Bit width for CRI = 0 or 1Wide-band CQI codeword 0 4 4 4 4 Subband differential CQI 2 2 2 2codeword 0 Wide-band CQI codeword 1 0 4 4 4 Subband differential CQI 0 22 2 codeword 1 Position of the M selected L L L L subbands Widebandfirst PMI i1 4 4 0 0 Wideband second PMI i2 4 4 4 4 Subband second PMIi2 4 4 4 4 Bit width for CRI = 2 Wide-band CQI of first set 4 4 4 4Subband differential CQI 2 2 2 2 of first set Wide-band CQI of secondset 4 4 4 4 Subband differential CQI 2 2 2 2 of second set Position ofthe M selected L L L L subbands Wideband first PMI i1 of 4 4 0 0 firstset Wideband second PMI i2 of 4 4 4 4 first set Wideband first PMI i1 of4 4 0 0 second set Wideband second PMI i2 of 4 4 4 4 second set Subbandsecond PMI i2 of 4 4 4 4 first set Subband second PMI i2 of 4 4 4 4second set

For the reporting sequence of the PMI and the CQI, refer to thereporting method 1 described above. To be specific, the CQI (includingthe CQI of the first set and the CQI of the second set) is firstreported, and then the PMI (including the PMI of the first set and thePMI of the second set) is reported. A reporting method 2 is describedbelow.

Reporting method 2: The first set (including the CQI and/or the PMI ofthe first set) is first reported, and then the second set (including theCQI and/or the PMI of the second set) is reported. The method 2 furtherincludes at least one of the following several specific methods:

Method 2.1: If the first set includes the CQI and the PMI, and thesecond set includes only the CQI, the CQI of the first set, the PMI ofthe first set, and the CQI of the second set are sequentially reported.

Method 2.2: If the first set includes the CQI, and the second setincludes the CQI and the PMI, the CQI of the first set, the CQI of thesecond set, and the PMI of the second set are sequentially reported.

Method 2.3: If the first set includes the CQI and the PMI, and thesecond set includes the CQI and the PMI, the CQI of the first set, thePMI of the first set, the CQI of the second set, and the PMI of thesecond set are sequentially reported.

The following describes cases in the three reporting modes for Reportingmethod 2. The three reporting modes are: the wideband CQI reportingmode, the higher layer-configured subband CQI reporting mode, and the UEselected subband CQI reporting mode. In one embodiment, at least one ofthe following methods may be used for at least one of the threereporting mode.

D. Wideband CQI Reporting Mode:

For wideband CQI reporting, when two CSI sets need to be reported, anexample of a reporting sequence in which the first set (including aCQI/PMI) is first reported, and then the second set (including aCQI/PMI) is reported is used below for description. Specifically, atleast one of the following manners may be used:

(D1) For the mode 1-2, the reporting manner may include at least oneitem in all tables shown in (D1).

In one embodiment, the mode 1-2 in the wideband CQI reporting mode maybe a feedback mode of a wideband CQI and a subband PMI.

For example, the following Table 5.2.2.6.1-1L-1-1 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 1-2 when the first indication information is configured andwhen the quantity of antenna ports is 2 or 4 and no R12 codebookenhancement is configured. Table 5.2.2.6.1-1L-2-3 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 1-2 when the first indication information is configured andwhen the quantity of antenna ports is 8. Table 5.2.2.6.1-1L-3-3 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 1-2 when the first indication information isconfigured and when the quantity of antenna ports is 4 and R12 codebookenhancement is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.1-1L-1-1 Scenarios for channel quality informationfeedback for wideband CQI and subband PMI reporting (Fields for channelquality information feedback for wideband CQI and subband PMI reports)(the transmission mode 10 is configured with PMI/RI reporting and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ with two/four antenna ports 2/4 with K > 1 and configured with thehigher layer parameter FeCoMPCSIEnabled except with configured R12codebook enhancement (transmission mode 10 configured with PMI/RIreporting and higher layer parameter eMIMO-Type, and eMIMO-Type is setto ‘CLASS B’ with 2/4 antenna ports with K > 1 and higher layerparameter FeCoMPCSIEnabled except with alternativeCodeBookEnabledFor4TX-r12 = TRUE)) 2 antenna ports 4 antenna ports Rank = Rank = Rank = Rank >Field 1 2 1 1 Bit width for CRI = 0 or 1 Wideband CQI codeword 0 4 4 4 4Wideband CQI codeword 1 0 4 0 4 Precoding matrix indicator   2N N   4N  4N Bit width for CRI = 2 Wideband CQI of first CSI set 4 4 4 4Precoding matrix indicator of   2N N   4N   4N first CSI set WidebandCQI of second CSI set 4 4 4 4 Precoding matrix indicator of   2N N   4N  4N second CSI set

TABLE 5.2.2.6.1-1L-2-3 Scenarios for channel quality informationfeedback for wideband CQI and subband PMI reporting (Fields for channelquality information feedback for wideband CQI and subband PMI reports)(the transmission mode 10 is configured with PMI/RI reporting and thehigher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASSB’ with eight antenna ports with K > 1 and configured with the higherlayer parameter FeCoMPCSIEnabled) Bit width for CRI = 0 or 1 Rank = Rank= Rank = Rank = Field 1 2 3 4 Wideband CQI codeword 0 4 4 4 4 WidebandCQI codeword 1 0 4 4 4 Wideband first PMI i1 4 4 2 2 Subband second PMIi2   4N   4N   4N   3N Bit width for CRI = 0 or 1 Rank = Rank = Rank =Rank = Field 5 6 7 8 Wideband CQI codeword 0 4 4 4 4 Wideband CQIcodeword 1 4 4 4 4 Wideband first PMI i1 2 2 2 0 Subband second PMI i2 00 0 0 Bit width for CRI = 2 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI of first set 4 4 4 4 Wideband first PMI i1 of 4 4 2 2 firstset Subband second PMI i2 of   4N   4N   4N   3N first set Wideband CQIof second set 4 4 4 4 Wideband first PMI i1 of 4 4 2 2 second setSubband second PMI i2 of   4N   4N   4N   3N second set

TABLE 5.2.2.6.1-1L-3-3 Scenarios for channel quality informationfeedback for wideband CQI and subband PMI reporting with four antennaports (Fields for channel quality information feedback for wideband CQIand subband PMI reports with 4 antenna ports) (the transmission mode 10is configured with PMI/RI reporting and the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with four antennaports with K > 1 and configured with the higher layer parameterFeCoMPCSIEnabled with configured R12 codebook enhancement (transmissionmode 10 configured with PMI/RI reporting and higher layer parametereMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with 4 antenna ports withK > 1, and higher layer parameter FeCoMPCSIEnabled withalternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank = Rank = Rank = Rank= Field 1 2 3 4 Bit width for CRI = 0 or 1 Wideband CQI codeword 0 4 4 44 Wideband CQI codeword 1 0 4 4 4 Wideband first PMI i1 4 4 0 0 Subbandsecond PMI i2   4N   4N   4N   4N Bit width for CRI = 2 Wideband CQI offirst set 4 4 4 4 Wideband first PMI i1 of 4 4 0 0 first set Subbandsecond PMI i2 of   4N   4N   4N   4N first set Wideband CQI of secondset 4 4 4 4 Wideband first PMI i1 of 4 4 0 0 second set Subband secondPMI i2 of   4N   4N   4N   4N second set

(D2) For the mode 1-0, the reporting manner may include at least oneitem in Table 5.2.2.6.1-1L-6-1 and Table 5.2.2.6.1-1L-7-1.

In one embodiment, the mode 1-0 in the wideband CQI reporting mode maybe a feedback mode of feedback of a wideband CQI and no feedback of aPMI.

For example, the following Table 5.2.2.6.1-1L-6-1 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 1-0 when the first indication information is configured andwhen the quantity of antenna ports is 1. Table 5.2.2.6.1-1L-7-1 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 1-0 when the first indication information isconfigured and when the quantity of antenna ports is 2/4/8 and no PMI/RIfeedback is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.1-1L-6-1 Scenarios for channel quality informationfeedback for wideband CQI reporting (Fields for channel qualityinformation feedback for wideband CQI reports) (the transmission mode 10is configured without PMI/RI reporting or configured with one antennaport and configured with the higher layer parameter FeCoMPCSIEnabled)Field Bit width for CRI = 0 or 1 Wide-band CQI 4 Bit width for CRI = 2Wide-band CQI of first set 4 Wide-band CQI of second set 4

TABLE 5.2.2.6.1-1L-7-1 Scenarios for channel quality informationfeedback for wideband CQI reporting (Fields for channel qualityinformation feedback for wideband CQI reports) (the transmission mode 10is configured without PMI reporting and configured with the higher layerparameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ withtwo/four/eight antenna ports and configured with the higher layerparameter FeCoMPCSIEnabled) Field Rank = 1 Rank > 1 Bit width for CRI =0 or 1 Wide-band CQI codeword 0 4 4 Wide-band CQI codeword 1 0 4 Bitwidth for CRI = 2 Wide-band CQI of first set 4 4 Wide-band CQI of secondset 4 4

(D3) For the mode 1-1, the reporting manner may include at least oneitem in all tables shown in (D3).

In one embodiment, the mode 1-1 in the wideband CQI reporting mode maybe a feedback mode of a wideband CQI and a wideband PMI.

For example, the following Table 5.2.2.6.1-1L-8 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode1-1 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. Table 5.2.2.6.1-1L-9 may be used to indicate a bit width forCSI feedback and/or a CSI feedback sequence in the mode 1-1 when thefirst indication information is configured and when the quantity ofantenna ports is 8. Table 5.2.2.6.1-1L-10 may be used to indicate a bitwidth for CSI feedback and/or a CSI feedback sequence in the mode 1-1when the first indication information is configured and when thequantity of antenna ports is 4 and R12 codebook enhancement isconfigured. CSI feedback in another configuration is also applicable.This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.1-1L-8 Scenarios for channel quality information feedbackfor wideband CQI reporting (Fields for channel quality informationfeedback for wideband CQI reports) (the transmission mode 10 isconfigured with PMI/RI reporting with two/four antenna ports andconfigured with the higher layer parameter eMIMO-Type, and eMIMO-Type isset to the ‘CLASS B’ with K > 1 and configured with the higher layerparameter FeCoMPCSIEnabled except with configured R12 codebookenhancement (transmission mode 10 configured with PMI/RI reporting with2/4 antenna ports and higher layer parameter eMIMO-Type, and eMIMO-Typeis set to ‘CLASS B’ with K > 1 and higher layer parameterFeCoMPCSIEnabled except with alternativeCodeBookEnabledFor4TX-r12 =TRUE)) 2 antenna ports 4 antenna ports Rank = Rank = Rank = Rank > Field1 2 1 1 Bit width for CRI = 0 or 1 Wide-band CQI codeword 0 4 4 4 4Wide-band CQI codeword 1 0 4 0 4 Precoding matrix indicator 2 1 4 4 Bitwidth for CRI = 2 Wide-band CQI of first set 4 4 4 4 Precoding matrixindicator of 2 1 4 4 first set Wide-band CQI of second set 4 4 4 4Precoding matrix indicator of 2 1 4 4 second set

TABLE 5.2.2.6.1-1L-9 Scenarios for channel quality information feedbackfor wideband CQI reporting (Fields for channel quality informationfeedback for wideband CQI reports) (the transmission mode 10 isconfigured with PMI/RI reporting with eight antenna ports and configuredwith the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ with K > 1 and configured with the higher layer parameterFeCoMPCSIEnabled) Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank =Field 1 2 3 4 Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 04 4 4 Wideband first PMI i1 4 4 2 2 Wideband second PMI i2 4 4 4 3Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 5 6 7 8Wideband CQI codeword 0 4 4 4 4 Wideband CQI codeword 1 4 4 4 4 Widebandfirst PMI i1 2 2 2 0 Wideband second PMI i2 0 0 0 0 Bitwidth for CRI = 2Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 4 44 4 Wideband first PMI i1 of 4 4 2 2 first set Wideband second PMI i2 of4 4 4 3 first set Wideband CQI of second set 4 4 4 4 Wideband first PMIi1 of 4 4 2 2 second set Wideband second PMI i2 of 4 4 4 3 second set

TABLE 5.2.2.6.1-1L-10 Scenarios for channel quality information feedbackfor wideband CQI reporting with four antenna ports (Fields for channelquality information feedback for wideband CQI reports with 4 antennaports) (the transmission mode 10 is configured with PMI/RI reportingwith four antenna ports and configured with the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with K > 1 andconfigured with the higher layer parameter FeCoMPCSIEnabled withconfigured R12 codebook enhancement (transmission mode 10 configuredwith PMI/RI reporting with 4 antenna ports and higher layer parametereMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with K > 1 and higherlayer parameter FeCoMPCSIEnabled withalternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank = Rank = Rank = Rank= Field 1 2 3 4 Bitwidth for CRI = 0 or 1 Wideband CQI codeword 0 4 4 44 Wideband CQI codeword 1 0 4 4 4 Wideband first PMI i1 4 4 0 0 Widebandsecond PMI i2 4 4 4 4 Bitwidth for CRI = 2 Wideband CQI of first set 4 44 4 Wideband first PMI i1 of 4 4 0 0 first set Wideband second PMI i2 of4 4 4 4 first set Wideband CQI of second set 4 4 4 4 Wideband first PMIi1 of 4 4 0 0 second set Wideband second PMI i2 of 4 4 4 4 second set

E. Higher Layer-Configured Subband CQI Reporting Mode:

For higher layer-configured subband CQI reporting, when two CSI setsneed to be reported, an example of a reporting sequence in which thefirst set (including a CQI/PMI) is first reported, and then the secondset (including a CQI/PMI) is reported is used below for description.Specifically, at least one of the following manners may be used:

(E1) For the mode 3-0, the reporting manner may include at least oneitem in Table 5.2.2.6.2-1B-1-1 and Table 5.2.2.6.2-1B-2-1.

In one embodiment, the mode 3-0 in the higher layer-configured subbandCQI reporting mode may be a feedback mode of feedback of a higherlayer-configured subband CQI and no feedback of a PMI.

For example, the following Table 5.2.2.6.2-1B-1-1 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 3-0 when the first indication information is configured andwhen the quantity of antenna ports is 1. Table 5.2.2.6.2-1B-2-1 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 3-0 when the first indication information isconfigured and when the quantity of antenna ports is 2/4/8 and no PMI/RIfeedback is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter. CSIfeedback in another configuration is also applicable. This is notspecifically limited herein.

TABLE 5.2.2.6.2-1B-1-1 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI reporting (Fields forchannel quality information feedback for higher layer configured subbandCQI reports) (the transmission mode 10 is configured without PMI/RIreporting or configured with one antenna port and configured with thehigher layer parameter FeCoMPCSIEnabled) Field Bit width for CRI = 0 or1 Wide-band CQI codeword 4 Subband differential CQI   2N Bit width forCRI = 2 Wide-band CQI of first set 4 Subband differential CQI of firstset   2N Wide-band CQI of second set 4 Subband differential CQI ofsecond set   2N

TABLE 5.2.2.6.2-1B-2-1 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI reporting (Fields forchannel quality information feedback for higher layer configured subbandCQI reports) (the transmission mode 10 is configured without PMI/RIreporting and configured with the higher layer parameter eMIMO-Type, andeMIMO-Type is set to the ‘CLASS B’ with two/four/eight antenna ports andconfigured with the higher layer parameter FeCoMPCSIEnabled) Field Rank= 1 Rank > 1 Bit width for CRI = 0 or 1 Wide-band CQI codeword 0 4 4Subband differential CQI codeword 0   2N   2N Wide-band CQI codeword 1 04 Subband differential CQI codeword 1 0   2N Bit width for CRI = 2Wide-band CQI of first set 4 4 Subband differential CQI of first set  2N   2N Wide-band CQI of second set 4 4 Subband differential CQI ofsecond set   2N   2N

(E2) For the mode 3-1, the reporting manner may include at least oneitem in all tables shown in (E2).

In one embodiment, the mode 3-1 in the higher layer-configured subbandCQI reporting mode may be a feedback mode of a higher layer-configuredsubband CQI and a wideband PMI.

For example, the following Table 5.2.2.6.2-2F-2 may be used to indicatea bit width for CSI feedback and/or a CSI feedback sequence in the mode3-1 when the first indication information is configured and when thequantity of antenna ports is 2 or 4 and no R12 codebook enhancement isconfigured. Table 5.2.2.6.2-2F-2-3 may be used to indicate a bit widthfor CSI feedback and/or a CSI feedback sequence in the mode 3-1 when thefirst indication information is configured and when the quantity ofantenna ports is 8. Table 5.2.2.6.2-2F-2-4 may be used to indicate a bitwidth for CSI feedback and/or a CSI feedback sequence in the mode 3-1when the first indication information is configured and when thequantity of antenna ports is 4 and R12 codebook enhancement isconfigured. CSI feedback in another configuration is also applicable.This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.2-2F-2 Scenarios for channel quality information feedbackfor higher layer-configured subband CQI reporting (Fields for channelquality information feedback for higher layer configured subband CQIreports) (the transmission mode 10 is configured with PMI/RI reportingwith two/four antenna ports and configured with the higher layerparameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ andconfigured with the higher layer parameter FeCoMPCSIEnabled except withconfigured R12 codebook enhancement (transmission mode 10 configuredwith PMI/RI reporting with 2/4 antenna ports and higher layer parametereMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with K > 1 and higherlayer parameter FeCoMPCSIEnabled except withaltemativeCodeBookEnabledFor4TX-r12 = TRUE)) 2 antenna ports 4 antennaports Rank = Rank = Rank = Rank > Field 1 2 1 1 Bit width for CRI = 0 or1 Wide-band CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N  2N   2N codeword 0 Wide-band CQI codeword 1 0 4 0 4 Subbanddifferential CQI 0   2N 0   2N codeword 1 Precoding matrix indicator 2 14 4 Bit width for CRI = 2 Wide-band CQI of first set 4 4 4 4 Subbanddifferential CQI of   2N   2N   2N   2N first set Precoding matrixindicator 2 1 4 4 of first set Wide-band CQI of second set 4 4 0 4Subband differential CQI of   2N   2N 0   2N second set Precoding matrixindicator 2 1 4 4 of second set

TABLE 5.2.2.6.2-2F-2-3 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI reporting (Fields forchannel quality information feedback for higher layer configured subbandCQI reports) (the transmission mode 10 is configured with PMI/RIreporting with eight antenna ports and configured with the higher layerparameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with K > 1and configured with the higher layer parameter FeCoMPCSIEnabled)Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 2 2 Widebandsecond PMI i2 4 4 4 3 Bitwidth for CRI = 0 or 1 Rank = Rank = Rank =Rank = Field 5 6 7 8 Wideband CQI codeword 0 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N codeword 0 Wideband CQI codeword 14 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword 1 Widebandfirst PMI i1 2 2 2 0 Wideband second PMI i2 0 0 0 0 Bitwidth for CRI = 2Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 4 44 4 Subband differential CQI of   2N   2N   2N   2N first set Widebandfirst PMI i1 of 4 4 2 2 first set Wideband second PMI i2 of 4 4 4 3first set Wideband CQI of second set 0 4 4 4 Subband differential CQI of0   2N   2N   2N second set Wideband first PMI i1 of 4 4 2 2 second setWideband second PMI i2 of 4 4 4 3 second set

TABLE 5.2.2.6.2-2F-2-4 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI reporting with fourantenna ports (Fields for channel quality information feedback forhigher layer configured subband CQI reports with 4 antenna ports) (thetransmission mode 10 is configured with PMI/RI reporting with fourantenna ports and configured with the higher layer parameter eMIMO-Type,and eMIMO-Type is set to the ‘CLASS B’ with K > 1 and configured withthe higher layer parameter FeCoMPCSIEnabled with configured R12 codebookenhancement (transmission mode 10 configured with PMI/RI reporting with4 antenna ports and higher layer parameter eMIMO- Type, and eMIMO-Typeis set to ‘CLASS B’ with K > 1 and higher layer parameterFeCoMPCSIEnabled with alternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank= Rank = Rank = Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1 WidebandCQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N   2Ncodeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI 0  2N   2N   2N codeword 1 Wideband first PMI i1 4 4 0 0 Wideband secondPMI i2 4 4 4 4 Bitwidth for CRI = 2 Wideband CQI of first set 4 4 4 4Subband differential CQI   2N   2N   2N   2N of first set Wideband firstPMI i1 of 4 4 0 0 first set Wideband second PMI i2 of 4 4 4 4 first setWideband CQI of second set 4 4 4 4 Subband differential CQI   2N   2N  2N   2N of second set Wideband first PMI i1 of 4 4 0 0 second setWideband second PMI i2 of 4 4 4 4 second set

(E3) For the mode 3-2, the reporting manner may include at least oneitem in all tables shown in (E3).

In one embodiment, the mode 3-2 in the higher layer-configured subbandCQI reporting mode may be a feedback mode of a higher layer-configuredsubband CQI and a subband PMI.

For example, the following Table 5.2.2.6.2-2G-1-3 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 3-2 when the first indication information is configured andwhen the quantity of antenna ports is 2 or 4 and no R12 codebookenhancement is configured. Table 5.2.2.6.2-2G-2-3 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 3-2 when the first indication information is configured andwhen the quantity of antenna ports is 8. Table 5.2.2.6.2-2G-3-3 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 3-2 when the first indication information isconfigured and when the quantity of antenna ports is 4 and R12 codebookenhancement is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.2-2G-1-3 Scenarios for channel quality informationfeedback for higher layer- configured subband CQI and subband PMIreporting (Fields for channel quality information feedback for higherlayer configured subband CQI and subband PMI reports) (the transmissionmode 10 is configured with subband PMI/RI reporting with two/fourantenna ports and configured with the higher layer parameter eMIMO-Type,and eMIMO- Type is set to ‘CLASS B’ with K > 1 and configured with thehigher layer parameter FeCoMPCSIEnabled except with configured R12codebook enhancement (transmission mode 10 configured with subbandPMI/RI reporting with 2/4 antenna ports and higher layer parametereMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with K > 1 and higherlayer parameter FeCoMPCSIEnabled except withalternativeCodeBookEnabledFor4TX-r12 = TRUE)) 2 antenna 4 antenna portsports Rank = Rank = Rank = Rank = Rank = Rank = Field 1 2 1 2 3 4 Bitwidth for CRI = 0 or 1 Wide-band 4 4 4 4   4   4   CQI codeword 0Subband   2N   2N   2N 2N 2N 2N differential CQI codeword 0 Wide-band 04 0 4   4   4   CQI codeword 1 Subband 0   2N 0 2N 2N 2N differentialCQI codeword 1 Subband   2N N   4N 4N 4N 4N precoding matrix indicatorBit width for CRI = 2 Wide-band 4 4 4 4   4   4   CQI of first setSubband   2N   2N   2N 2N 2N 2N differential CQI of first set Subband  2N N   4N 4N 4N 4N precoding matrix indicator of first set Wide-band 44 4 4   4   4   CQI of second set Subband   2N   2N   2N 2N 2N 2Ndifferential CQI of second set Subband   2N N   4N 4N 4N 4N precodingmatrix indicator of second set

TABLE 5.2.2.6.2-2G-2-3 Scenarios for channel quality informationfeedback for higher layer- configured subband CQI and subband PMIreporting with eight antenna ports (Fields for channel qualityinformation feedback for higher layer configured subband CQI and subbandPMI reports with 8 antenna ports) (the transmission mode 10 isconfigured with PMI/RI reporting and configured with the higher layerparameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with K > 1and configured with the higher layer parameter FeCoMPCSIEnabled)Bitwidth for CRI = 0 or 1 Rank = Rank = Rank = Rank = Field 1 2 3 4Wideband CQI codeword 0 4 4 4 4 Subband differential CQI   2N   2N   2N  2N codeword 0 Wideband CQI codeword 1 0 4 4 4 Subband differential CQI0   2N   2N   2N codeword 1 Wideband first PMI i1 4 4 2 2 Subband secondPMI i2   4N   4N   4N   3N Bitwidth for CRI = 0 or 1 Rank = Rank = Rank= Rank = Field 5 6 7 8 Wideband CQI codeword 0 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N codeword 0 Wideband CQI codeword 14 4 4 4 Subband differential CQI   2N   2N   2N   2N codeword 1 Widebandfirst PMI i1 2 2 2 0 Subband second PMI i2 0 0 0 0 Bitwidth for CRI = 2Rank = Rank = Rank = Rank = Field 1 2 3 4 Wideband CQI of first set 4 44 4 Subband differential CQI   2N   2N   2N   2N of first set Widebandfirst PMI i1 of 4 4 2 2 first set Subband second PMI i2 of   4N   4N  4N   3N first set Wideband CQI of second set 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N of second set Wideband first PMI i1of 4 4 2 2 second set Subband second PMI i2 of   4N   4N   4N   3Nsecond set

TABLE 5.2.2.6.2-2G-3-3 Scenarios for channel quality informationfeedback for higher layer-configured subband CQI and subband PMIreporting with four antenna ports (Fields for channel qualityinformation feedback for higher layer configured subband CQI and subbandPMI reports with 4 antenna ports) (the transmission mode 10 isconfigured with PMI/RI reporting with two/four antenna ports andconfigured with the higher layer parameter eMIMO-Type, and eMIMO-Type isset to the ‘CLASS B’ with K > 1 and configured with the higher layerparameter FeCoMPCSIEnabled with configured R12 codebook enhancement(transmission mode 10 configured with subband PMI/RI reporting with 2/4antenna ports and higher layer parameter eMIMO-Type, and eMIMO-Type isset to ‘CLASS B’ with K > 1 and higher layer parameter FeCoMPCSIEnabledwith alternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank = Rank = Rank =Rank = Field 1 2 3 4 Bitwidth for CRI = 0 or 1 Wideband CQI codeword 0 44 4 4 Subband differential CQI   2N   2N   2N   2N codeword 0 WidebandCQI codeword 1 0 4 4 4 Subband differential CQI 0   2N   2N   2Ncodeword 1 Wideband first PMI i1 4 4 0 0 Subband second PMI i2   4N   4N  4N   4N Bitwidth for CRI = 2 Wideband CQI of first set 4 4 4 4 Subbanddifferential CQI   2N   2N   2N   2N of first set Wideband first PMI i1of 4 4 0 0 first set Subband second PMI i2 of   4N   4N   4N   4N firstset Wideband CQI of second set 4 4 4 4 Subband differential CQI   2N  2N   2N   2N of second set Wideband first PMI i1 of 4 4 0 0 second setSubband second PMI i2 of   4N   4N   4N   4N second set

F. UE Selected Subband CQI Reporting Mode:

For UE selected subband CQI reporting, for example, if UE selects Msubbands, feedback of positions of the M selected subbands may befinally performed after two CSI sets, may be performed after the firstCSI set and before the second CSI set, or may be performed before thetwo CSI sets. This is not specifically limited.

In one embodiment, for the positions of the M selected subbands, onlyone reporting parameter may be fed back for two CSI sets, and theparameter is used to indicate the positions of the M selected subbands.Alternatively, each of the CSI sets may include one reporting parameter,and the reporting parameter is used to indicate the positions of the Mselected subbands. This is not specifically limited herein.

An example of a reporting sequence of the first set (including aCQI/PMI), the second set (including a CQI/PMI), and the positions of theM selected subbands is used below for description.

(F1) For the mode 2-0, the reporting manner may include at least oneitem in Table 5.2.2.6.3-1B-1-1 and Table 5.2.2.6.3-1B-2-1.

In one embodiment, the mode 2-0 in the UE selected subband CQI reportingmode may be a feedback mode of feedback of a UE selected subband CQI andno feedback of a PMI.

For example, the following Table 5.2.2.6.3-1B-1-1 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 1-0 when the first indication information is configured andwhen the quantity of antenna ports is 1. Table 5.2.2.6.3-1B-2-1 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 1-0 when the first indication information isconfigured and when the quantity of antenna ports is 2/4/8 and no PMI/RIfeedback is configured. CSI feedback in another configuration is alsoapplicable. This is not specifically limited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.3-1B-1-1 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting (Fields for channelquality information feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured without PMI/RI reporting orconfigured with one antenna port and configured with the higher layerparameter FeCoMPCSIEnabled) Field Bit width for CRI = 0 or 1 Wide-bandCQI codeword 4 Subband differential CQI 2 Position of the M selectedsubbands L Bit width for CRI = 2 Wide-band CQI of first set 4 Subbanddifferential CQI of first set 2 Wide-band CQI of second set 4 Subbanddifferential CQI of second set 2 Position of the M selected subbands L

TABLE 5.2.2.6.3-1B-2-1 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting (Fields for channelquality information feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured without PMI reporting or configuredwith one antenna port and configured with the higher layer parametereMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with two/four/eightantenna ports and configured with the higher layer parameterFeCoMPCSIEnabled) Field Rank = 1 Rank > 1 Bit width for CRI = 0 or 1Wide-band CQI codeword 0 4 4 Subband differential CQI codeword 0 2 2Wide-band CQI codeword 1 0 4 Subband differential CQI codeword 1 0 2Position of the M selected subbands L L Bit width for CRI = 2 Wide-bandCQI of first set 4 4 Subband differential CQI of first set 2 2 Wide-bandCQI of second set 4 4 Subband differential CQI of second set 2 2Position of the M selected subbands L L

(F2) For the mode 2-2, the reporting manner may include at least oneitem in all tables shown in (F2).

In one embodiment, the mode 2-2 in the UE selected subband CQI reportingmode may be a feedback mode of a wideband CQI and a subband PMI.

For example, the following Table 5.2.2.6.3-2K-1-4 may be used toindicate a bit width for CSI feedback and/or a CSI feedback sequence inthe mode 2-2 when the first indication information is configured andwhen the quantity of antenna ports is 2 or 4 and no R12 codebookenhancement is configured. At least one of Table 5.2.2.6.3-2K-2-4 may beused to indicate a bit width for CSI feedback and/or a CSI feedbacksequence in the mode 2-2 when the first indication information isconfigured and when the quantity of antenna ports is 8. At least one ofTable 5.2.2.6.3-2K-3-4 may be used to indicate a bit width for CSIfeedback and/or a CSI feedback sequence in the mode 2-2 when the firstindication information is configured and when the quantity of antennaports is 4 and R12 codebook enhancement is configured. CSI feedback inanother configuration is also applicable. This is not specificallylimited herein.

In one embodiment, the terminal may store at least one item in thefollowing table. When the terminal configures a corresponding parameter,the terminal may determine a bit width for CSI feedback and/or a CSIfeedback sequence based on a table corresponding to the parameter.

TABLE 5.2.2.6.3-2K-1-4 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting (Fields for channelquality information feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting with two/fourantenna ports and configured with the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the ‘CLASS B’ with K > 1 and configuredwith the higher layer parameter FeCoMPCSIEnabled except with configuredR12 codebook enhancement (transmission mode 10 configured with PMI/RIreporting with 2/4 antenna ports and higher layer parameter eMIMO-Type,and eMIMO-Type is set to ‘CLASS B’ with K > 1, and higher layerparameter FeCoMPCSIEnabled except with alternativeCodeBookEnabledFor4TX-r12 = TRUE)) 2 antenna ports 4 antenna ports Rank = Rank = Rank = Rank >Field 1 2 1 1 Bit width for CRI = 0 or 1 Wide-band CQI codeword 0 4 4 44 Subband differential CQI 2 2 2 2 codeword 0 Wide-band CQI codeword 1 04 0 4 Subband differential CQI 0 2 0 2 codeword 1 Position of the Mselected L L L L subbands Precoding matrix indicator 4 2 8 8 Bit widthfor CRI = 2 Wide-band CQI of first set 4 4 4 4 Subband differential CQIof 2 2 2 2 first set Precoding matrix indicator of 4 2 8 8 first setWide-band CQI of second set 4 4 4 4 Subband differential CQI of 2 2 2 2second set Precoding matrix indicator of 4 2 8 8 second set Position ofthe M selected L L L L subbands

TABLE 5.2.2.6.3-2K-2-4 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting (Fields for channelquality information feedback for UE selected subband CQI reports) (thetransmission mode 10 is configured with PMI/RI reporting with eightantenna ports and configured with the higher layer parameter eMIMO-Type,and eMIMO-Type is set to the ‘CLASS B’ with K > 1 and configured withthe higher layer parameter FeCoMPCSIEnabled) Rank = Rank = Rank = Rank =Rank = Rank = Rank = Rank = Field 1 2 3 4 5 6 7 8 Bit width for CRI = 0or 1 Wide-band 4 4 4 4 4 4 4 4 CQI codeword 0 Subband 2 2 2 2 2 2 2 2differential CQI codeword 0 Wide-band 0 4 4 4 4 4 4 4 CQI codeword 1 Bitwidth for CRI = 0 or 1 Subband 0 2 2 2 2 2 2 2 differential CQI codeword1 Position of L L L L L L L L the M selected subbands Wideband 4 4 2 2 22 2 0 first PMI i1 Wideband 4 4 4 3 0 0 0 0 second PMI i2 Subband 4 4 43 0 0 0 0 second PMI i2 Bit width for CRI = 2 Rank = Rank = Rank = Rank= Field 1 2 3 4 Wide-band CQI of first set 4 4 4 4 Subband differentialCQI of first set 2 2 2 2 Wideband first PMI i1 of first set 4 4 2 2Wideband second PMI i2 of first set 4 4 4 3 Subband second PMI i2 offirst set 4 4 4 3 Wide-band CQI of second set 4 4 4 4 Subbanddifferential CQI of second set 2 2 2 2 Wideband first PMI i1 of secondset 4 4 2 2 Wideband second PMI i2 of second set 4 4 4 3 Subband secondPMI i2 of second set 4 4 4 3 Position of the M selected subbands L L L L

TABLE 5.2.2.6.3-2K-3-4 Scenarios for channel quality informationfeedback for UE selected subband CQI reporting with four antenna ports(Fields for channel quality information feedback for UE selected subbandCQI reports with 4 antenna ports) (the transmission mode 10 isconfigured with PMI/RI reporting with four antenna ports and configuredwith the higher layer parameter eMIMO-Type, and eMIMO-Type is set to the‘CLASS B’ with K > 1 and configured with the higher layer parameterFeCoMPCSIEnabled with configured R12 codebook enhancement (transmissionmode 10 configured with PMI/RI reporting with 4 antenna ports and higherlayer parameter eMIMO-Type, and eMIMO-Type is set to ‘CLASS B’ with K >1, and higher layer parameter FeCoMPCSIEnabled withalternativeCodeBookEnabledFor4TX-r12 = TRUE)) Rank = Rank = Rank = Rank= Field 1 2 3 4 Bit width for CRI = 0 or 1 Wide-band CQI codeword 0 4 44 4 Subband differential CQI 2 2 2 2 codeword 0 Wide-band CQI codeword 10 4 4 4 Subband differential CQI 0 2 2 2 codeword 1 Position of the Mselected L L L L subbands Wideband first PMI i1 4 4 0 0 Wideband secondPMI i2 4 4 4 4 Subband second PMI i2 4 4 4 4 Bit width for CRI = 2Wide-band CQI of first set 4 4 4 4 Subband differential CQI of 2 2 2 2first set Wideband first PMI i1 of 4 4 0 0 first set Wideband second PMIi2 of 4 4 4 4 first set Subband second PMI i2 of 4 4 4 4 first setWide-band CQI of second set 4 4 4 4 Subband differential CQI of 2 2 2 2second set Wideband first PMI i1 of 4 4 0 0 second set Wideband secondPMI i2 of 4 4 4 4 second set Subband second PMI i2 of 4 4 4 4 second setPosition of the M selected L L L L subbands

In addition, the CSI measurement behavior in this embodiment of thepresent disclosure includes FeCoMP (or non-coherent transmission, forexample, non-coherent joint transmission NCJT)-based CSI measurement. AFeCoMP (or non-coherent transmission) feature is introduced to theprotocol release R15. In this case, for terminal devices supporting theprotocol release R15, because of different capabilities of the terminaldevices, some terminal devices may not support FeCoMP (or non-coherenttransmission) due to limitations of capabilities such as hardwarestorage or processing capabilities, and some terminal devices have astrong capability and can support FeCoMP (or non-coherent transmission).Therefore, this embodiment of the present disclosure provides asolution: When accessing a network, the terminal device may reportwhether FeCoMP (or non-coherent transmission)-based CSI measurementand/or feedback are/is supported, as a capability of the terminal deviceto the network device, so that the network device can learn whether theterminal supports FeCoMP (or non-coherent transmission)-based CSImeasurement and/or feedback or supports FeCoMP (or non-coherenttransmission)-based transmission. This embodiment may be implemented incombination with another embodiment provided in the present disclosure,or may be separately implemented. This is not specifically limited.

In addition, this embodiment of the present disclosure further providesanother solution: When accessing a network, the terminal device mayreport a QCL type supported by the terminal device, as a capability ofthe terminal device to the network device, so that the network devicecan learn whether the terminal device supports FeCoMP (or non-coherenttransmission)-based transmission. For example, in the protocol releaseR15, in addition to the QCL types A and B, the QCL type C is furtherintroduced. The terminal device may report, by using RRC signaling, aQCL type supported by the terminal device. If the terminal devicereports that the QCL type C is supported, it indicates that the terminaldevice supports FeCoMP (or non-coherent transmission)-basedtransmission. If the terminal reports that the QCL type A or B issupported, it indicates that the terminal device supports single-celltransmission or CoMP dynamic point selection/blanking (DPS/DPB)single-point transmission. This embodiment may be implemented incombination with another embodiment provided in the present disclosure,or may be separately implemented. This is not specifically limited.

FIG. 10B is a flowchart of a method for reporting a capability of aterminal device.

Operation 1001: The terminal device sends third indication informationto a network device, and the network device receives the thirdindication information from the terminal device. The third indicationinformation is used to indicate whether the terminal device supportsFeCoMP-based CSI measurement and/or feedback.

For example, when accessing a network, the terminal device may send thethird indication information to the network device. In animplementation, the terminal device may send the third indicationinformation by using RRC signaling.

Operation 1002: The network device determines, based on the thirdindication information, a QCL type supported by the terminal device,and/or determines whether the terminal device supports FeCoMP-based CSImeasurement and/or feedback. If the terminal device supportsFeCoMP-based CSI measurement and/or feedback, operation 1003 isperformed; otherwise, this procedure ends.

For example, in the third indication information, information used toindicate whether the terminal device supports FeCoMP-based CSImeasurement and/or feedback is 1 bit carried in RRC signaling. If avalue of the 1 bit is “1” or “TRUE”, it indicates that the terminaldevice supports FeCoMP-based CSI measurement and/or feedback; or if thevalue of the 1 bit is “0” or “FALSE”, it indicates that the terminaldevice does not support FeCoMP-based CSI measurement and/or feedback.

Alternatively, if RRC signaling carries the 1-bit third indicationinformation, it indicates that the terminal device supports FeCoMP-basedCSI measurement and/or feedback. If RRC signaling does not carry thethird indication information, or carried third indication informationdoes not include information used to indicate whether the terminaldevice supports FeCoMP-based CSI measurement and/or feedback, itindicates that the terminal device does not support FeCoMP-based CSImeasurement and/or feedback. Certainly, the 1 bit herein is merely anexample, and a quantity of bits used for capability indicationinformation is not limited in this embodiment of the present disclosure.

For another information, in the third indication information,information used to indicate the QCL type supported by the terminaldevice is two bits carried in RRC signaling. If a value of the 2 bits is“00”, it indicates that the QCL type supported by the terminal device isa QCL type A; if a value of the 2 bits is “01”, it indicates that theQCL type supported by the terminal device is a QCL type B; or if a valueof the 2 bits is “10”, it indicates that the QCL type supported by theterminal device is a QCL type C. A mapping relationship between the bitvalue and the indicated QCL type herein is merely an example, and thatthe information used to indicate the QCL type supported by the terminaldevice is 2 bits is also merely an example, which are not limited inthis embodiment of the present disclosure.

Operation 1003: When the network device determines that the terminaldevice supports FeCoMP-based CSI measurement and/or feedback, ordetermines that the QCL type supported by the terminal device is the QCLtype C (which also indicates that the terminal device supportsFeCoMP-based CSI measurement and/or feedback), the network device sends,to the terminal device, information indicating that FeCoMP-based CSImeasurement and feedback are supported, and the terminal devicereceives, from the network device, the information indicating thatFeCoMP-based CSI measurement feedback is supported. For example, theindication information is the first indication information described inthe foregoing embodiment.

Further, the method further includes the following operations:

Operation 1004: The network device sends DCI for scheduling datatransmission in FeCoMP to the terminal device, and the terminal devicereceives the DCI, where indication information in the DCI includes atleast two groups of QCL parameters, or a QCL quantity indicated in theDCI is greater than 1.

Operation 1005: The network device and the terminal device perform NCJTtransmission.

According to the technical solution provided in this embodiment of thepresent disclosure, the network device can learn whether the terminaldevice supports FeCoMP (or non-coherent transmission, for example,NCJT)-based CSI measurement, so that the network device can perform NCJTtransmission with the terminal device that supports FeCoMP-based CSImeasurement, thereby improving a transmission success rate.

According to the foregoing method, FIG. 11 is a first schematic diagramof a device according to an embodiment of the present disclosure. Asshown in FIG. 11 , the device may be a terminal device 10, or may be achip or a circuit, for example, a chip or a circuit that can be disposedin a terminal device. The terminal device 10 may correspond to theterminal device in the foregoing method.

The device may include a processor 110 and a memory 120. The memory 120is configured to store an instruction, and the processor 110 isconfigured to execute the instruction stored in the memory 120, toimplement the operations in the foregoing method, for example, themethod corresponding to at least one of FIG. 5-1 , FIG. 5-3 , or FIG.10B.

Further, the device may include an input port 140 and an output port150. Further, the device may further include a bus system 130. Theprocessor 110, the memory 120, the input port 140, and the output port150 may be connected by using the bus system 130.

The processor 110 is configured to execute the instruction stored in thememory 120, to control the input port 140 to receive a signal andcontrol the output port 150 to send a signal, to complete the operationsof the terminal device in the foregoing method. The input port 140 andthe output port 150 may be a same physical entity or different physicalentities. When the input port 140 and the output port 150 are the samephysical entity, the input port 140 and the output port 150 may becollectively referred to as an input/output port. The memory 120 may beintegrated into the processor 110, or may be separated from theprocessor 110.

In an implementation, it may be considered that functions of the inputport 140 and the output port 150 are implemented by a transceivercircuit or a dedicated transceiver chip. It may be considered that theprocessor 110 is implemented by a dedicated processing chip, processingcircuit, or processor, or a general-purpose chip.

In another implementation, it may be considered that the terminal deviceprovided in this embodiment of the present disclosure is implemented bya general-purpose computer. To be specific, program code that implementsfunctions of the processor 110, the input port 140, and the output port150 is stored in the memory, and a general-purpose processor implementsthe functions of the processor 110, the input port 140, and the outputport 150 by executing the code in the memory.

For concepts, explanations, detailed descriptions, and other operationsthat are related to the technical solutions provided in this embodimentof the present disclosure and that are related to the device, refer torelated descriptions of the content in the foregoing method or anotherembodiment. Details are not described herein again.

FIG. 12 is a schematic structural diagram of a terminal device accordingto the present disclosure. The terminal device is applicable to thecommunications system to which the embodiments of the present disclosureare applicable, for example, the 5G communications system shown in FIG.3 or FIG. 4 ; for another example, an LTE communications system. Forease of description, FIG. 12 shows only main components of the terminaldevice. As shown in FIG. 12 , the terminal device 10 includes aprocessor, a memory, a control circuit, an antenna, and an input/outputapparatus. The processor is mainly configured to: process acommunication protocol and communication data, control the entireterminal device, execute a software program, and process data of thesoftware program, for example, is configured to support the terminaldevice in performing the action described in the foregoing embodiment ofthe communications method. The memory is mainly configured to store thesoftware program and the data, for example, store predefined relatedinformation described in the foregoing embodiments. The control circuitis mainly configured to: perform conversion between a baseband signaland a radio frequency signal and process the radio frequency signal. Thecontrol circuit, together with an antenna, may also be referred to as atransceiver that is mainly configured to send and receive a radiofrequency signal in an electromagnetic wave form. The input/outputapparatus, such as a touchscreen, a display screen, or a keyboard, ismainly configured to: receive data entered by a user, and output data tothe user.

After the terminal device is powered on, the processor may read asoftware program in a storage unit, explain and execute an instructionof the software program, and process data of the software program. Whendata needs to be sent wirelessly, the processor performs basebandprocessing on the to-be-sent data, and then outputs a baseband signal toa radio frequency circuit. The radio frequency circuit performs radiofrequency processing on the baseband signal, and then sends a radiofrequency signal in an electromagnetic wave form through the antenna.When data is sent to the terminal device, the radio frequency circuitreceives a radio frequency signal through the antenna, converts theradio frequency signal into a baseband signal, and outputs the basebandsignal to the processor. The processor converts the baseband signal intodata, and processes the data.

A person skilled in the art may understand that for ease of description,FIG. 12 shows only one memory and one processor. Actually, the terminaldevice may include a plurality of processors and a plurality ofmemories. The memory may also be referred to as a storage medium, astorage device, or the like. This is not limited in this embodiment ofthe present disclosure.

In one embodiment, the processor may include a baseband processor and acentral processing unit. The baseband processor is mainly configured toprocess the communication protocol and the communication data, and thecentral processing unit is mainly configured to: control the entireterminal device, execute the software program, and process the data ofthe software program. The processor in FIG. 12 is integrated withfunctions of the baseband processor and the central processing unit. Aperson skilled in the art may understand that the baseband processor andthe central processing unit may alternatively be processors independentof each other, and are interconnected by using a technology such as abus. A person skilled in the art may understand that the terminal devicemay include a plurality of baseband processors to adapt to differentnetwork standards, the terminal device may include a plurality ofcentral processing units to improve a processing capability of theterminal device, and components of the terminal device may be connectedby using various buses. The baseband processor may also be expressed asa baseband processing circuit or a baseband processing chip. The centralprocessing unit may also be expressed as a central processing circuit ora central processing chip. A function of processing the communicationprotocol and the communication data may be embedded into the processor,or may be stored in a storage unit in a form of a software program, sothat the processor executes the software program to implement a basebandprocessing function.

For example, in this embodiment of the present disclosure, the antennaand the control circuit that have receiving and sending functions may beconsidered as a transceiver unit 101 of the terminal device 10, and theprocessor having a processing function may be considered as a processingunit 102 of the terminal device 10. As shown in FIG. 12 , the terminaldevice 10 includes the transceiver unit 101 and the processing unit 102.The transceiver unit may also be referred to as a transceiver, atransceiver apparatus, or the like. In one embodiment, a component thatis in the transceiver unit 101 and that is configured to implement areceiving function is considered as a receiving unit, and a componentthat is in the transceiver unit 101 and that is configured to implementa sending function is considered as a sending unit. In other words, thetransceiver unit 101 includes the receiving unit and the sending unit.For example, the receiving unit may also be referred to as a receiver, areceiver, a receiver circuit, or the like, and the sending unit may alsobe referred to as a transmitter, a transmitter, a transmit circuit, orthe like.

According to the foregoing method, FIG. 13 is a second schematic diagramof a device according to an embodiment of the present disclosure. Asshown in FIG. 13 , the device may be a network device 20, or may be achip or a circuit, for example, a chip or a circuit that can be disposedin a network device. The network device 20 corresponds to the networkdevice in the foregoing method. The device may include a processor 210and a memory 220. The memory 220 is configured to store an instruction,and the processor 210 is configured to execute the instruction stored inthe memory 220, so that the device implements the foregoing method, forexample, the method corresponding to at least one of FIG. 5-1 , FIG. 5-3, or FIG. 10B.

Further, the network device may further include an input port 240 and anoutput port 250. Further, the network may further include a bus system230.

The processor 210, the memory 220, the input port 240, and the outputport 250 are connected by using the bus system 230. The processor 210 isconfigured to execute the instruction stored in the memory 220, tocontrol the input port 240 to receive a signal and control the outputport 250 to send a signal, to complete the operations of the networkdevice in at least one of the foregoing methods. The input port 240 andthe output port 250 may be a same physical entity or different physicalentities. When the input port 240 and the output port 250 are the samephysical entity, the input port 240 and the output port 250 may becollectively referred to as an input/output port. The memory 220 may beintegrated into the processor 210, or may be separated from theprocessor 210.

In an implementation, it may be considered that functions of the inputport 240 and the output port 250 are implemented by a transceivercircuit or a dedicated transceiver chip. It may be considered that theprocessor 210 is implemented by a dedicated processing chip, processingcircuit, or processor, or a general-purpose chip.

In another implementation, it may be considered that the network deviceprovided in this embodiment of the present disclosure is implemented bya general-purpose computer. To be specific, program code that implementsfunctions of the processor 210, the input port 240, and the output port250 is stored in the memory, and a general-purpose processor implementsthe functions of the processor 210, the input port 240, and the outputport 250 by executing the code in the memory.

For concepts, explanations, detailed descriptions, and other operationsthat are related to the technical solutions provided in this embodimentof the present disclosure and that are related to the device, refer torelated descriptions of the content in the foregoing method or anotherembodiment. Details are not described herein again.

According to the foregoing method, FIG. 14 is a schematic structuraldiagram of a network device according to an embodiment of the presentdisclosure, for example, may be a schematic structural diagram of a basestation. As shown in FIG. 14 , the base station is applicable to thecommunications system to which the embodiments of the present disclosureare applicable, for example, the 5G communications system shown in FIG.3 or FIG. 4 ; for another example, an LTE communications system. Thebase station 20 includes one or more radio frequency units, for example,an RRU 201 and one or more baseband units (BBU) (which may also bereferred to as a digital unit, DU) 202. The RRU 201 may be referred toas a transceiver unit, a transceiver, a transceiver circuit, atransceiver, or the like, and may include at least one antenna 2011 andat least one radio frequency unit 2012. The RRU 201 is mainly configuredto: send and receive a radio frequency signal and perform conversionbetween a radio frequency signal and a baseband signal, for example,configured to send the signaling message in the foregoing embodiments toa terminal device. The BBU 202 is mainly configured to: perform basebandprocessing, control the network device, and so on. The RRU 201 and theBBU 202 may be physically disposed together, or may be physicallyseparated, namely, a distributed base station.

The BBU 202 is a control center of the base station, or may be referredto as a processing unit, and is mainly configured to complete basebandprocessing functions such as channel coding, multiplexing, modulation,and spectrum spreading. For example, the BBU (the processing unit) maybe configured to control the base station to perform an operationprocedure of the network device in the foregoing method embodiments.

For example, the BBU 202 may include one or more boards, and a pluralityof boards may jointly support a radio access network (such as an LTEnetwork) of a single access standard, or may separately support radioaccess networks of different access standards. The BBU 202 furtherincludes a memory 2021 and a processor 2022. The memory 2021 isconfigured to store an instruction and data that are suitable. Forexample, the memory 2021 stores predefined related information in theforegoing embodiments. The processor 2022 is configured to control thebase station to perform a suitable action, for example, is configured tocontrol the base station to perform an operation procedure related tothe network device in the foregoing method embodiments. The memory 2021and the processor 2022 may serve the one or more boards. In other words,a memory and a processor may be independently disposed on each board.Alternatively, the plurality of boards may share a same memory and asame processor. In addition, each board may further be provided with asuitable circuit.

According to the method provided in the embodiments of the presentdisclosure, an embodiment of the present disclosure further provides acommunications system. The system includes the foregoing network deviceand one or more terminal devices.

It should be understood that in the embodiments of the presentdisclosure, the processor may be a central processing unit (CPU), or theprocessor may be another general-purpose processor, a digital signalprocessor (DSP), an application-specific integrated circuit (ASIC), afield programmable gate array (FPGA), or another programmable logicdevice, discrete gate or transistor logic device, discrete hardwarecomponent, or the like. The general-purpose processor may be amicroprocessor, or the processor may be any conventional processor orthe like.

The memory may include a read-only memory and a random access memory,and provide an instruction and data to the processor. A part of thememory may further include a non-volatile random access memory.

The bus system may further include a power bus, a control bus, a statussignal bus, and the like, in addition to a data bus. However, for cleardescription, various types of buses in the figure are marked as the bussystem.

In an implementation process, the operations in the foregoing methodscan be implemented by a hardware integrated logic circuit in theprocessor, or by using instructions in a form of software. Theoperations of the method disclosed with reference to the embodiments ofthe present disclosure may be directly performed by a hardwareprocessor, or may be performed by using a combination of hardware in theprocessor and a software module. The software module may be located in amature storage medium in the art, such as a random access memory, aflash memory, a read-only memory, a programmable read-only memory, anelectrically erasable programmable memory, or a register. The storagemedium is located in the memory, and the processor reads information inthe memory and completes the operations in the foregoing methods incombination with hardware of the processor. To avoid repetition, detailsare not described herein again.

It should be further understood that “first”, “second”, “third”,“fourth”, and various numerical symbols in this specification are merelyused for differentiation for ease of description, and are not construedas a limitation on the scope of the embodiments of the presentdisclosure.

It should be understood that sequence numbers of the foregoing processesdo not mean execution sequences in various embodiments of the presentdisclosure. The execution sequences of the processes should bedetermined based on functions and internal logic of the processes, andshould not be construed as any limitation on the implementationprocesses of the embodiments of the present disclosure.

A person of ordinary skill in the art may be aware that, in combinationwith illustrative logical blocks described in the embodiments disclosedin this specification and operations (operation) may be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether the functions are performed by hardware or softwaredepends on particular applications and design constraint conditions ofthe technical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of the present disclosure.

It may be clearly understood by a person skilled in the art that, forthe purpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, refer to acorresponding process in the foregoing method embodiments, and detailsare not described herein again.

In the several embodiments provided in the present disclosure, it shouldbe understood that the disclosed systems, apparatuses, and methods maybe implemented in other manners. For example, the described apparatusembodiments are merely examples. For example, the unit division ismerely logical function division and may be other division in actualimplementation. For example, a plurality of units or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented through some interfaces. The indirect couplings orcommunication connections between the apparatuses or units may beimplemented in electronic, mechanical, or other forms.

The units described as separate parts may or may not be physicallyseparate, and parts displayed as units may or may not be physical units,may be located in one position, or may be distributed on a plurality ofnetwork units. Some or all of the units may be selected based on actualrequirements to achieve the objectives of the solutions of theembodiments.

In addition, functional units in the embodiments of the presentdisclosure may be integrated into one processing unit, or each of theunits may exist alone physically, or two or more units are integratedinto one unit.

All or some of the foregoing embodiments may be implemented by software,hardware, firmware, or any combination thereof. When software is used toimplement the embodiments, the embodiments may be implemented completelyor partially in a form of a computer program product. The computerprogram product includes one or more computer instructions. When thecomputer program instructions are loaded and executed on the computer,the procedures or functions according to the embodiments of the presentdisclosure are all or partially generated. The computer may be ageneral-purpose computer, a special-purpose computer, a computernetwork, or other programmable apparatuses. The computer instructionsmay be stored in a computer-readable storage medium or may betransmitted from a computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(DSL)) or wireless (for example, infrared, radio, and microwave, or thelike) manner. The computer-readable storage medium may be any usablemedium accessible by a computer, or a data storage device, such as aserver or a data center, integrating one or more usable media. Theusable medium may be a magnetic medium (for example, a floppy disk, ahard disk, or a magnetic tape), an optical medium (for example, a DVD),a semiconductor medium (for example, a solid-state drive (SSD)), or thelike.

The foregoing descriptions are merely specific implementations of thepresent disclosure, but are not intended to limit the protection scopeof the present disclosure. Any variation or replacement readily figuredout by a person skilled in the art within the technical scope disclosedin the present disclosure shall fall within the protection scope of thepresent disclosure. Therefore, the protection scope of the presentdisclosure shall be subject to the protection scope of the claims.

What is claimed is:
 1. A communications method, comprising: receivingfirst indication information from a network device; and determiningchannel state information (CSI) feedback related information based onthe first indication information, wherein the CSI feedback relatedinformation comprises bit meaning of a CSI-reference signal resourceindicator (CRI), wherein the first indication information is used toenable further enhancements to coordinated multi point based CSIfeedback.
 2. The method according to claim 1, wherein the CSI feedbackrelated information further comprises at least one of a bit width of aCRI, a bit width of a rank indicator (RI), a bit meaning of a CRI, or abit meaning of an RI.
 3. The method according to claim 2, wherein thedetermining CSI feedback related information based on the firstindication information comprises: determining at least one of the bitwidth of the CRI, or the bit meaning of the CRI based on the firstindication information; or determining the bit width of the RI based onthe first indication information and at least one of a quantity ofantenna ports for a non-zero power (NZP) CSI-reference signal (CSI-RS),capability information of a terminal device; or determining the bitmeaning of the RI based on the first indication information and at leastone of the bit width of the RI, or a value of the CRI.
 4. The methodaccording to claim 3, wherein the determining at least one of the bitwidth of the CRI, or the bit meaning of the CRI based on the firstindication information comprises: determining the bit width of the CRIis 2 based on the first indication information; or, determining the bitmeaning of the CRI based on the first indication information as follows:CRI=0 indicating that reported CSI is obtained through measurement basedon a first NZP CSI-RS resource; or, CRI=1 indicating that reported CSIis obtained through measurement based on a second NZP CSI-RS resource;or, CRI=2 indicating that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource and the second NZP CSI-RSresource.
 5. The method according to claim 3, wherein determining thebit meaning of the RI based on the first indication information and thevalue of the CRI comprises: when the first indication information isused to enable further enhancements to coordinated multi point based CSIfeedback, when CRI=0 or 1, determining one RI is fed back; when CRI=2,determining two RIs are fed back.
 6. The method according to claim 2,further comprising: determining, based on the first indicationinformation, to feed back at least two CSI sets, wherein the at leasttwo CSI sets comprise a first set of CSI and a second set of CSI, andthe CSI comprises a channel quality indicator (CQI) and/or a precodingmatrix indicator (PMI); a feedback sequence of the at least two CSI setsis that a CQI of the first set, a CQI of the second set, a PMI of thefirst set, and a PMI of the second set are sequentially fed back; andthe first set of CSI corresponds to CSI for a first NZP CSI-RS resource,and the second set of CSI corresponds to CSI for a second NZP CSI-RSresource; or the first set of CSI corresponds to CSI for a firstcodeword, and the second set of CSI corresponds to CSI for a secondcodeword.
 7. The method according to claim 2, wherein the method furthercomprises: sending third indication information to the network device,wherein the third indication information indicates a quasi-co-location(QCL) type supported by a terminal device, or indicates that furtherenhancements to coordinated multi point based CSI feedback is supported.8. A communications method, comprising: sending first indicationinformation; and determining channel state information (CSI) feedbackrelated information and receiving, based on the CSI feedback relatedinformation, CSI feedback from a terminal device, wherein the CSIfeedback related information is related to the first indicationinformation, wherein the CSI feedback related information comprises bitmeaning of a CSI-reference signal resource indicator (CRI), and whereinthe first indication information is used to enable further enhancementsto coordinated multi point based CSI feedback.
 9. The method accordingto claim 8, wherein the CSI feedback related information furthercomprises at least one of a bit width of a CRI, a bit width of a rankindicator (RI), a bit meaning of a CRI, or a bit meaning of an RI. 10.The method according to claim 9, wherein that the CSI feedback relatedinformation is related to the first indication information comprises: atleast one of the bit width of the CRI, or the bit meaning of the CRI isrelated to the first indication information; or the bit width of the RIis related to the first indication information and at least one of aquantity of antenna ports for a non-zero power (NZP) CSI-referencesignal (CSI-RS), capability information of the terminal device; or thebit meaning of the RI is related to the first indication information andat least one of the bit width of the RI, or a value of the CRI.
 11. Themethod according to claim 10, wherein at least one of the bit width ofthe CRI, or the bit meaning of the CRI is related to the firstindication information comprises: when the first indication informationis used to enable FeCoMP-based CSI feedback, the bit width of the CRI is2; or, when the first indication information is used to enableFeCoMP-based CSI feedback, the bit meaning of the CRI is as follows:CRI=0 indicating that reported CSI is obtained through measurement basedon a first NZP CSI-RS resource; or, CRI=1 indicating that reported CSIis obtained through measurement based on a second NZP CSI-RS resource;or, CRI=2 indicating that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource and the second NZP CSI-RSresource.
 12. The method according to claim 10, wherein the bit meaningof the RI is related to the first indication information and the valueof the CRI comprises: when the first indication information is used toenable further enhancements to coordinated multi point based CSIfeedback, when CRI=0 or 1, one RI is fed back; when CRI=2, two RIs arefed back.
 13. The method according to claim 10, further comprising:determining that at least two CSI sets fed back by the terminal deviceare related to the first indication information, wherein the at leasttwo CSI sets comprise a first set of CSI and a second set of CSI, andthe CSI comprises a channel quality indicator (CQI) and/or a precodingmatrix indicator (PMI); a feedback sequence of the at least two CSI setsis that a CQI of the first set, a CQI of the second set, a PMI of thefirst set, and a PMI of the second set are sequentially fed back; andthe first set of CSI corresponds to CSI for a first NZP CSI-RS resource,and the second set of CSI corresponds to CSI for a second NZP CSI-RSresource; or the first set of CSI corresponds to CSI for a firstcodeword, and the second set of CSI corresponds to CSI for a secondcodeword.
 14. The method according to claim 9, further comprising:receiving third indication information from the terminal device, whereinthe third indication information indicates a quasi-co-location (QCL)type supported by the terminal device, or indicates that furtherenhancements to coordinated multi point based CSI feedback is supported.15. A communications apparatus, comprising: a receiver configured toreceive first indication information from a network device; and aprocessor configured to determine channel state information (CSI)feedback related information based on the first indication information,wherein the CSI feedback related information comprises bit meaning of aCSI-reference signal resource indicator (CRI), and wherein the firstindication information is used to enable further enhancements tocoordinated multi point based CSI feedback.
 16. The communicationsapparatus according to claim 15, wherein the CSI feedback relatedinformation further comprises at least one of a bit width of a CRI, abit width of a rank indicator (RI), a bit meaning of a CRI, or a bitmeaning of an RI.
 17. The communications apparatus according to claim16, wherein in determining CSI feedback related information based on thefirst indication information, the processor is configured to: determineat least one of the bit width of the CRI, or the bit meaning of the CRIbased on the first indication information; or determine the bit width ofthe RI based on the first indication information and at least one of aquantity of antenna ports for a non-power (NZP) CSI-reference signal(CSI-RS), capability information of a terminal device; or determine thebit meaning of the RI based on the first indication information and atleast one of the bit width of the RI, or a value of the CRI.
 18. Thecommunications apparatus according to claim 17, wherein in determiningat least one of the bit width of the CRI, or the bit meaning of the CRIbased on the first indication information, the processor is configuredto: determine the bit width of the CRI is 2, when the first indicationinformation is used to enable FeCoMP-based CSI feedback; or, determinethe bit meaning of the CRI, when the first indication information isused to enable FeCoMP-based CSI feedback, as follows: CRI=0 indicatingthat reported CSI is obtained through measurement based on a first NZPCSI-RS resource; or, CRI=1 indicating that reported CSI is obtainedthrough measurement based on a second NZP CSI-RS resource; or, CRI=2indicating that reported CSI is obtained through measurement based onthe first NZP CSI-RS resource and the second NZP CSI-RS resource. 19.The communications apparatus according to claim 17, wherein indetermining the bit meaning of the RI based on the first indicationinformation and the value of the CRI, the processor is configured to:determine one RI is fed back, when CRI=0 or 1; determine two RIs are fedback, when CRI=2; when the first indication information is used toenable further enhancements to coordinated multi point based CSIfeedback.
 20. The communications apparatus according to claim 16, theprocessor is further configured to: determine, based on the firstindication information, to feed back at least two CSI sets, wherein theat least two CSI sets comprise a first set of CSI and a second set ofCSI, and the CSI comprises a channel quality indicator (CQI) and/or aprecoding matrix indicator (PMI); a feedback sequence of the at leasttwo CSI sets is that a CQI of the first set, a CQI of the second set, aPMI of the first set, and a PMI of the second set are sequentially fedback; and the first set of CSI corresponds to CSI for a first NZP CSI-RSresource, and the second set of CSI corresponds to CSI for a second NZPCSI-RS resource; or the first set of CSI corresponds to CSI for a firstcodeword, and the second set of CSI corresponds to CSI for a secondcodeword.
 21. The communications apparatus according to claim 16,further comprising: a transmitter, configured to send third indicationinformation to the network device, wherein the third indicationinformation indicates a quasi-co-location (QCL) type supported by aterminal device, or indicates that further enhancements to coordinatedmulti point based CSI feedback is supported.
 22. A communicationapparatus, comprising: a transmitter configured to send first indicationinformation; a processor configured to determine channel stateinformation (CSI) feedback related information; and a receiverconfigured to receive, based on the CSI feedback related information,CSI feedback from a terminal device, wherein the CSI feedback relatedinformation is related to the first indication information, wherein theCSI feedback related information comprises bit meaning of aCSI-reference signal resource indicator (CRI), and wherein the firstindication information is used to enable further enhancements tocoordinated multi point based CSI feedback.
 23. The communicationapparatus according to claim 22, wherein the CSI feedback relatedinformation further comprises at least one of a bit width of a CRI, abit width of a rank indicator (RI), a bit meaning of a CRI, or a bitmeaning of an RI.
 24. The communication apparatus according to claim 23,wherein the CSI feedback related information is related to the firstindication information comprises: at least one of the bit width of theCRI, or the bit meaning of the CRI is related to the first indicationinformation; or the bit width of the RI is related to the firstindication information and at least one of a quantity of antenna portsfor a non-zero power (NZP) CSI-reference signal (CSI-RS), capabilityinformation of the terminal device; or the bit meaning of the RI isrelated to the first indication information and at least one of the bitwidth of the RI, or a value of the CRI.
 25. The communication apparatusaccording to claim 24, wherein at least one of the bit width of the CRI,or the bit meaning of the CRI is related to the first indicationinformation comprises: when the first indication information is used toenable further enhancements to coordinated multi point based CSIfeedback, the bit width of the CRI is 2; or, when the first indicationinformation is used to enable further enhancements to coordinated multipoint based CSI feedback, the bit meaning of the CRI is as follows:CRI=0 indicating that reported CSI is obtained through measurement basedon a first NZP CSI-RS resource; or, CRI=1 indicating that reported CSIis obtained through measurement based on a second NZP CSI-RS resource;or, CRI=2 indicating that reported CSI is obtained through measurementbased on the first NZP CSI-RS resource and the second NZP CSI-RSresource.
 26. The communication apparatus according to claim 24, whereinthe bit meaning of the RI is related to the first indication informationand the value of the CRI comprises: when the first indicationinformation is used to enable further enhancements to coordinated multipoint based CSI feedback, when CRI=0 or 1, one RI is fed back; whenCRI=2, two RIs are fed back.
 27. The communication apparatus accordingto claim 23, the processor is further configured to: determine that atleast two CSI sets fed back by the terminal device are related to thefirst indication information, wherein the at least two CSI sets comprisea first set of CSI and a second set of CSI, and the CSI comprises achannel quality indicator (CQI) and/or a precoding matrix indicator(PMI); a feedback sequence of the at least two CSI sets is that a CQI ofthe first set, a CQI of the second set, a PMI of the first set, and aPMI of the second set are sequentially fed back; and the first set ofCSI corresponds to CSI for a first NZP CSI-RS resource, and the secondset of CSI corresponds to CSI for a second NZP CSI-RS resource; or thefirst set of CSI corresponds to CSI for a first codeword, and the secondset of CSI corresponds to CSI for a second codeword.
 28. Thecommunication apparatus according to claim 23, the receiver is furtherconfigured to: receive third indication information from the terminaldevice, wherein the third indication information indicates aquasi-co-location (QCL) type supported by the terminal device, orindicates that further enhancements to coordinated multi point based CSIfeedback is supported.